Here is the quote on the picture, followed by its context and more (all-caps added for emphasis):
“Unbelief will ever find cause to doubt and reason away THE MOST POSITIVE PROOF.” (The Spirit of Prophecy Volume Two, p. 278, by Ellen G. White)
“This interview of Jesus with his disciples, in which they had received much precious instruction, was interrupted by those who had been searching for him. As the people began to flock about him, bringing their sick and afflicted, he repaired to the synagogue. While he was teaching there, many others of those who had left him on the other side of the lake came to the synagogue, and were surprised to see Jesus and his disciples there before them, knowing that there was no boat by which he could pass to the other side. They began to inquire how and when he had crossed the sea. They were astonished when the disciples related to them the events of the preceding night. The fury of the storm and the many hours of fruitless rowing against the fury of adverse winds, the appearance of Christ walking upon the water, the fears thus aroused, his reassuring words, the adventure of Peter and its result, with the sudden stilling of the tempest and landing of the boat, were all faithfully recounted to the wondering crowd, amid frequent interruptions and exclamations of amazement.
“But their attention was now directed to the lessons of Jesus, so full of solemn interest. Many were deeply affected; but the minds of some were entirely engrossed with curiosity regarding the wonderful relation they had heard. As soon as the discourse was ended, they gathered around the Saviour, questioning him, hoping to receive from his own lips a fuller account of his mighty work of the previous night. But Jesus did not gratify their idle curiosity. He was also beset by the Pharisees, to show them a sign from Heaven that he was the Son of God. They asked an evidence of his miraculous power, such as had been given on the other side of the sea. They importuned him to repeat his wonderful works before them.
“Jesus declared to them that they did not seek him from any worthy motive; that they did not desire to learn how to please God in their daily lives; but they asked him to work miracles, sometimes in a spirit of unbelief, and sometimes because they hoped to be benefited by temporal favors which he might thus bestow upon them. He bade them not to labor for the meat which perishes, but to seek for spiritual food, that wisdom which endures unto everlasting life. This the Son of God alone could give, for he has the seal of the Father. With solemn earnestness he sought to impress upon them that temporal favors are of little consequence compared with the heavenly grace offered by the Son of God.
“‘Then said they unto him, What shall we do, that we might work the works of God? Jesus answered and said unto them, This is the work of God, that ye believe on Him whom he hath sent. They said therefore unto him, What sign showest thou then, that we may see, and believe thee? what dost thou work? Our fathers did eat manna in the desert; as it is written, He gave them bread from heaven to eat.’ It was Christ himself who conducted the Hebrews in their travels through the wilderness. It was he who had daily fed them manna from heaven; yet they blindly referred him to this miracle, wrought for their fathers, in a spirit of caviling unbelief. Jesus declared to them that as God had given them manna to preserve their lives, so he had sent to them this gift of his Son, that through him they might eat of the bread of life and become immortal.
“‘Then said Jesus unto them, Verily, verily, I say unto you, Moses gave you not that bread from heaven; but my Father giveth you the true bread from Heaven. For the bread of God is He which cometh down from Heaven, and giveth life unto the world. Then said they unto him, Lord, evermore give us this bread.’ Jesus used bread as a figure to illustrate the vitalizing power of his Spirit. The one sustains physical life, while the other satisfies the heart, and strengthens the moral powers. Said he, ‘I am the bread of life; he that cometh to me shall never hunger; and he that believeth on me shall never thirst. But I said unto you, That ye also have seen me, and believe not.’ Those who experience the spiritual union with Christ never hunger for higher enjoyment. All uncertainty is gone, the weary soul finds continual refreshment in the Saviour. The feverish thirst for wealth and honor is gone. He is in them a well of water springing up into everlasting life.
“Jesus assured the Jews that they had seen him and his works yet believed not. He did not refer to their seeing him with their natural eyes; but he meant that their understanding had been convinced, while their proud and stubborn hearts refused to acknowledge him as the Messiah. The Saviour had been doing in their midst works that no man had ever done. The living evidences of his divine power had been before them day after day; yet their hard and caviling hearts asked for still another sign of his divinity before they would believe. Had this been given them they would still have remained as unbelieving as before. If they were not already convinced of his Messiahship by what they had seen and heard, it was useless to show them more marvelous works. The dignity of God’s holy Son was not to be compromised to gratify a questioning crowd.
“Said Jesus, ‘For this people’s heart is waxed gross, and their ears are dull of hearing, and their eyes they have closed; lest at any time they should see with their eyes, and hear with their ears, and should understand with their heart, and should be converted, and I should heal them.’ UNBELIEF WILL EVER FIND CAUSE TO DOUBT AND REASON AWAY THE MOST POSITIVE PROOF. The Jews stood constantly upon guard, lest they should be forced by overwhelming evidence to yield their prejudice and unbelief. Though their understanding was convinced, they refused to surrender their pride and self-righteousness, admitting that they, who had boasted of their wisdom over all the rest of the world, themselves needed a teacher.
“The Jews had assembled to celebrate the passover. In eating the flesh of the lamb, they were to remember that it represented the Lamb of God, and their protection when the first-born of their enemies were slain in Egypt. The blood that the Hebrews were commanded to have upon their door-posts, and which was a sign of safety to them, also represented the blood of Christ, which was to be shed for the sins of the world. The Saviour has power to finally raise from the dead all those who, by faith, eat of his flesh and drink of his blood. This spiritual food gives to the believers a well-founded hope of the resurrection to immortal life in the kingdom of God.
“These precious truths Jesus declared to the incredulous multitude, saying, ‘All that the Father giveth me shall come to me; and him that cometh to me I will in no wise cast out. For I came down from Heaven, not to do mine own will, but the will of him that sent me. And this is the Father’s will which hath sent me, that of all which he hath given me I should lose nothing, but should raise it up again at the last day. And this is the will of Him that sent me, that every one which seeth the Son, and believeth on him, may have everlasting life, and I will raise him up at the last day.’
“He spoke of his future sacrifice in these words: ‘And the bread which I will give you, is my flesh, which I will give for the life of the world.’ He offered his salvation to all who would accept him, clothed in humanity, as their Redeemer, having access to the Father, and being invested by him with divine authority.
“But the Jews were displeased that Jesus should claim to be the bread of life come down from Heaven. ‘And they said, Is not this Jesus, the son of Joseph, whose father and mother we know? how is it, then, that he saith, I came down from Heaven?’ They so clung to their bigotry and pride that it now seemed impossible for them to believe evidence that was plain as the noonday sun. Their jealousy was aroused that this man of humble birth was able to work wonders that they could not explain away, and teach truths that could not be contradicted. So they endeavored to awaken the prejudice and unbelief of the people by referring scornfully to the lowly origin of Jesus, and by reason of his mysterious birth, insinuating that he was of doubtful parentage. They contemptuously alluded to his life as a Galilean laborer, and to his family as being poor and lowly. They declared that the lofty claims of this uneducated carpenter should be at once repudiated.
“But Jesus heard their murmurings and reproved them. He again, in more forcible language, declared his connection with the Father, and the necessity for the heart to be enlightened by the Spirit of God before it can feel the need of a Saviour. ‘No man can come to me, except the Father which hath sent me draw him; and I will raise him up at the last day. It is written in the prophets, And they shall be all taught of God. Every man, therefore, that hath heard, and hath learned of the Father, cometh unto me.’ He here refers to the prophecy of Isaiah: ‘And all thy children shall be taught of the Lord, and great shall be the peace of thy children.’
“This was not a new doctrine which Jesus taught. It was the fulfillment of prophecy, which, as expounders of the word, the priests and elders should have thoroughly understood. In declaring that none come to him unless the Father draws them, the Saviour wished them to understand that God would never appear in person to teach them concerning the way of life. Humanity could not endure the vision of his glory for a moment; only through the Son could they come to him. In seeing and hearing the Son, they saw and heard the Father. He is Mediator between God and his disobedient children. The Jews claimed God as their teacher, but Christ declared such profession vain, for, said he, ‘Every man, therefore, that hath heard, and hath learned of the Father, cometh unto me.’
“Jesus did not attempt to answer the questions raised regarding his birth any more than he had answered those concerning his crossing the sea. He did not desire to magnify himself, nor the miracles that marked his life. The prejudice of the Pharisees lay deeper than their questions would indicate, and had taken root in the bitter perversity of their sinful hearts. His sayings and doings had not created such feelings, but only called them into action, because his pure and elevated doctrine was not in harmony with their selfish hearts. Said he, ‘Verily, verily, I say unto you, He that believeth on me hath everlasting life. I am that bread of life.’ There were conflicting views and much uncertainty in regard to the resurrection of the dead. Aside from the dissension between the Sadducees and Pharisees, the Jews were in great darkness concerning the future life and the resurrection of the body. Jesus pitied them in their benighted condition, and bade them accept him, who was their only hope, the great Life-giver, even the ‘bread of life.’
“They had referred him to the manna which their fathers ate in the wilderness, as if the furnishing of that food was a greater miracle than Jesus had wrought; but he now declared unto them that the temporal food then given from Heaven was but a meager gift compared with the blessing of eternal life which he now offered them. The food eaten then sustained the strength, but did not prevent the approach of death, nor insure immortal life. The bread that the Son of God offered to man was death-destroying, giving in the end immortal life to the body. Said he, ‘Your fathers did eat manna in the wilderness, and are dead. This is the bread which cometh down from Heaven, that a man may eat thereof, and not die. I am the living bread which came down from Heaven; if any man eat of this bread, he shall live forever; and the bread that I will give is my flesh, which I will give for the life of the world.’
“Our Lord here points forward to his approaching death, the only true propitiation for the sins of humanity. The Jews were about to celebrate with great display the feast of the passover. The lamb to be eaten there, was a symbol of Christ’s body; yet the very person that it represented stood in their midst, presenting himself as their Saviour, whose blood would preserve them from the wrath of a sin-hating God, and they refuse his offers of mercy.
“The miracle Jesus had performed in feeding the multitude, furnished him a forcible figure by which to illustrate his work upon earth. He declared that, as temporal bread imparts health and strength to the body, so will faith in Christ, and obedience to his teachings, give spiritual vigor to the soul, and life everlasting. But the Jews, determined to misinterpret his words, now engaged in angry contention, asking, ‘How can this man give us his flesh to eat?’ They affected to understand his words in the same literal sense as did Nicodemus, when he asked, ‘How can a man be born when he is old?’ They comprehended the meaning of Jesus, but were not willing to acknowledge it. They thought it a favorable opportunity to prejudice the people against him, by presenting his words to them in the most unfavorable light. ‘Then Jesus said unto them, Verily, verily, I say unto you, Except ye eat the flesh of the Son of Man, and drink his blood, ye have no life in you. Whoso eateth my flesh, and drinketh my blood, hath eternal life; and I will raise him up at the last day. For my flesh is meat indeed, and my blood is drink indeed. He that eateth my flesh, and drinketh my blood, dwelleth in me, and I in him. As the living Father hath sent me, and I live by the Father, so he that eateth me, even he shall live by me. This is that bread which came down from Heaven; not as your fathers did eat manna, and are dead; he that eateth of this bread shall live forever.’
“The Jews appeared to be horrified at these sayings of Christ. Their law strictly forbade them to taste blood, and they construed his language into a sacrilegious speech, and contended and disputed over his words among themselves. Jesus gave his disciples, and the people, lessons which they could not at the time fully comprehend, because of their moral darkness. Many things which his followers did not fully understand when he uttered them, were made plain by subsequent events. His words were a stay to their hearts when he walked no more with them.
“Even the disciples murmured at these last words of Jesus. They said, ‘This is a hard saying; who can hear it?’ The Saviour heard their complaints and answered them: ‘Doth this offend you? What and if ye shall see the Son of Man ascend up where he was before? It is the spirit that quickeneth; the flesh profiteth nothing; the words that I speak unto you, they are spirit, and they are life.’ Thus he instructed them that it was not his human flesh that would give life eternal, but faith in his words and in the efficacy of the sacrifice he was to make for the world. His teaching and example, his life and death, were the heavenly food that was to give them spiritual life and vigor. He reproved them because they had murmured when he said that he had come down from Heaven. If they were not able to receive this truth, how would it be when he ascended before their eyes to that Heaven from whence he came?
“Jesus knew that many followed him who hoped to receive temporal favors thereby. They looked for him to work some miracle that would benefit them; but especially did they hope that he would eventually free them from the Roman yoke. He also knew that there was one near who would betray him. He told them that there were some among them who believed not. ‘And he said, Therefore said I unto you, that no man can come unto me, except it were given unto him of my Father.’
“He wished them to understand that their hearts must be open to the Spirit of God before they could be drawn to him by faith. They must be willing to have their errors reproved, to eschew evil, and lead holy lives. The unbelief existing among the priests and rulers influenced the people to be hesitating and doubtful. Jesus had given them sufficient proof of his divinity; but their incredulous minds were ever seeking to explain away his wonderful works. They reasoned that the disciples might have been under a delusion when they saw him walking upon the water.
“True, they could not but admit that he had performed many miraculous cures, and plentifully fed a vast multitude from five loaves and two small fishes; but their dissatisfied hearts queried, if he could do these wonders, why might he not give health, strength, and riches to all his people, free them from their oppressors, and exalt them to power and honor? Then they would believe on him and glorify his name. Thus they allowed themselves to be bound by unbelief and discontent. Their gross minds refused to comprehend the meaning of his words, ‘I am the bread which came down from Heaven.’ His doctrine was too pure and exalted to attract their carnal hearts.
“This discourse of Jesus cooled the enthusiasm of the people. If, by becoming his disciples, they must live righteous lives, deny self, and suffer humiliation, they had no desire to rally under his banner. Alas for Israel! They knew not the time of their visitation! They refused their Saviour, because they longed for a conqueror who would give them temporal power. They wanted the meat which perishes, and not that which endures unto everlasting life. Their ambition was for earthly riches and glory, and they had no relish for the words of Christ that taught personal purity, and a thorough reformation of life.
“Many of the words and dealings of Jesus appear mysterious to finite minds; but all his purposes were clear to his divine understanding. His whole plan was mapped before him, perfect in all its details. Every act was calculated to produce its individual results. The history of the world from its creation to the end of time was fully known to Christ. Were the mind of man capable of understanding his dealings, every act of his earthly life would stand forth important, complete, and in harmony with his divine mission.
“The murmuring of his followers grieved the heart of the Saviour. In openly rebuking their unbelief before the multitude, he had increased their disaffection, and many of them went back and walked no more with Jesus. He looked after these erring ones with eyes of pitying tenderness. They were greatly displeased, and, wishing to wound Jesus and gratify the malice of the Pharisees, they turned their backs upon him and left him with disdain. In doing this they made the fatal mistake of rejecting God’s counsel to them. It was such developments as these that made the Saviour a Man of sorrows and acquainted with grief. The consciousness that his kindness and compassion were unappreciated, his love unrequited, his mercy slighted, his salvation rejected, filled his divine soul with a grief that was inexpressible. Could these ungrateful disciples have discerned how God viewed their behavior to his dear Son, they would hardly have walked away so proudly and defiantly. They were choosing darkness rather than light, because they were too vain and self-righteous to receive a merited rebuke, and too worldly to accept a life of humility in order to secure salvation. In the face of all his wonderful works they turned away from Him, who, by the beauty of his doctrine and his mercy and benevolence, had called thousands to his side; who had relieved suffering humanity, so that entire cities and villages were freed from disease, and there was no work for a physician among them.
“When we view the generosity of Christ to the poor and suffering, his patience with the rude and ignorant, his self-denial and sacrifice, we are lost in admiration and reverence. What a gift has God lavished upon man, alienated from him by sin and disobedience! Well may the heart break and the tears flow in contemplation of such inexpressible love! Christ abased himself to humanity that he might reach man sunken into the depths of woe and degradation, and lift him into a nobler life, give him moral strength to resist the power of Satan and overcome sin in his name. Sad was the recompense he met for his marvelous condescension.
“The words of Jesus were scorned because he declared that outward professions and observances of forms would not avail; the work must reach the heart and bring forth fruit meet for repentance. The words that he addressed to his disciples are also spoken to the followers of Christ today. The same necessity exists for a clean heart and a pure life. Yet how many reject the warning of God, spoken by his servants, and the close, practical truths pressed home to their hearts, because their lives are not in accordance with the will of God, because they perceive that an entire reformation is necessary, and are unwilling to take up the self-denying work, and are therefore angry because their sins have been discovered. They go away offended, even as the disciples left Jesus, murmuring, ‘This is a hard saying; who can hear it?’
“Those who profess godliness, yet do not heed the admonitions of the Lord, nor regulate their lives in harmony with his holy will, fasten themselves more and more firmly by chains of darkness. Many who now profess to believe the truth of Christ, endure the test no better than those who turned away from following him. Many, while professing the faith, are so separated from Christ by hearts of unbelief, that they reject the words and works of God shown through his servants. If the divine revelation does not harmonize with their views, they feel at liberty to turn from its teachings. If it rebukes their sins they are offended. Praise and flattery would be grateful to their ears, but the truth is disagreeable, they cannot hear it. When the crowds follow, and the multitudes are fed, and the cries of triumph go up, their voices are loud in praise; but when the searching of God’s Spirit reveals to them their sin and bids them leave it, they turn their backs upon the truth, and ‘walk no more with Jesus.’
“God does not propose to be called to account for his ways and works. It is for his glory to conceal his purposes now; but by and by they will be revealed in their true importance. But he has not concealed his great love, which lies at the foundation of all his dealings with his children. He has revealed his love in the gift of his Son, and in the many providences by which he manifests himself. He who lives near to Jesus may understand much of the mystery of godliness, and comprehend the love that administers merited reproof. Humanity, alienated from God, can only be reconciled to him by partaking spiritually of the flesh and blood of his dear Son.
“The Saviour did not attempt to prevent the disaffected disciples from leaving him, but, turning to the twelve chosen ones, said sorrowfully, ‘Will ye also go away?’ Peter promptly replied by asking in turn ‘Lord, to whom shall we go? Thou hast the words of eternal life, and we believe and are sure that thou art that Christ, the Son of the living God.’ How full of meaning are these words, ‘To whom shall we go?’ The teachers of Israel were slaves to cold formality. The Pharisees and Sadducees were in constant contention concerning the doctrine of the resurrection and other points of difference. To leave Jesus was to fall among sticklers for rites and ceremonies, and ambitious men who sought their own glory. The disciples had felt more peace and joy since they had accepted Christ than in all their previous lives. They had looked back with horror upon their former course of carelessness and iniquity. How could they, whose eyes had been opened to discern the malice and bigotry of the Jews, go back to them who had scorned and persecuted the Friend of sinners? Long had their faith sustained them in looking for the Messiah, and now that he had come, they could not turn from his presence to those who were hunting his life and had persecuted them for obeying him.
“ ‘To whom shall we go?’ Not from the doctrine of Christ, his lessons of love and charity, to the darkness of unbelief, the wickedness of the world. While many were turning from the Saviour who had witnessed his miraculous works, who had seen him heal the sick and comfort the distressed, who had been electrified by the heavenly majesty of his bearing, Peter expresses the faith of the disciples, ‘Thou art that Christ.’ Never will they deny that he is the world’s Redeemer, the Son of God. The very thought of losing this anchor of their souls thrilled their hearts with anguish. To be again destitute of a Saviour, subject to fear and superstition, would be to be adrift upon a dark and stormy sea.
“Some may question the wisdom of Jesus in introducing a subject so easily misunderstood as that which had turned so many from him on this occasion. But he had a purpose in view. He saw that a most trying ordeal awaited his disciples in his betrayal, his agony in Gethsemane, and his crucifixion. He knew who among his followers were unbelieving and who were of weak faith. Had no test been given them, Jesus would have had many among his followers who were weak in character, and undecided. When the great trial came, and their Lord was betrayed and condemned in the Judgment Hall; when he was humiliated, and the multitude, who had hailed him as their king, hissed at him and reviled him; when the cruel, jeering crowd cried, ‘Crucify him!’–then these faint-hearted ones would have sunk beneath their fear and disappointment.
“The apostasy of these professed followers of Christ at such a time, would have been more than the twelve could have endured in addition to their great grief and the terrible ruin of their fondest hopes. The example of those who turned from him, might, in that hour of horror, have carried all the rest with them. But Jesus brought about this crisis while he was still present to comfort and strengthen his chosen, and prepare them for what was to follow. When the hooting rabble scorned Him who was doomed to the cross, the disciples were not overwhelmed with surprise at this insult to their Master, for they had seen the fickleness of those who had once followed him. When those who had professed to love the Master turned from him in the time of his trouble, the disciples remembered that the same thing had occurred before, for less reason. They had tested the inconstant favor of the world, and hung not their faith upon the opinions of others. Jesus wisely prepared the minds of his faithful few for the great trial of his betrayal and death.
“Peter had great faith in Jesus. From the first he had believed that he was the Messiah. He had seen and heard John, who was the forerunner of Christ, proclaim him to be the Lamb of God that taketh away the sins of the world. He had been closely connected with Jesus, had witnessed his miracles, listened to his teachings, and was convinced that he was the Son of God Many who had been convicted by the preaching of John, and had accepted Christ, began to doubt as to the mission of John, when he was imprisoned and put to death. They also doubted if Jesus was really the Messiah, whom they had looked for so long.
“But the faith of Peter never flagged; he followed his Master with unwavering devotion. When those of the disciples who had ardently expected Jesus to make a great display of power, and take his place on David’s throne, left him because they perceived that he had no such intention, Peter and his companions faltered not in their allegiance. The vacillating course of those who praised yesterday, and condemned today, did not affect the faith of the true follower of the Saviour. Peter declares, ‘Thou art the Son of the living God.’ He waited not for kingly honors to crown his Lord, but accepted him in his humiliation. Peter, in his confession of Christ, expressed the faith of the disciples. But notwithstanding this, Jesus knew that neither his believing followers nor any of the Jews had any idea of associating humiliation, suffering and death, with their Messiah. Compassionate Redeemer, who, in the full knowledge of the doom that awaited him, tenderly smoothed the way for his disciples, prepared them for their crowning trial, and strengthened them for the final test! ” (The Spirit of Prophecy Volume Two, pp. 274-291, by Ellen G. White)