Jesus answered them and said, "Verily, verily, I say unto you, Ye seek me, not because ye saw the miracles, but because ye did eat of the loaves, and were filled.
 Labour not for the meat which perisheth, but for that meat which endureth unto everlasting life, which the Son of man shall give unto you: for him hath God the Father sealed."
 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."
In the practice of art, as well as in morals, it is necessary to keep a watchful and jealous eye over ourselves; idleness, assuming the specious disguise of industry, will lull to sleep all suspicion of our want of an active exertion of strength. A provision of endless apparatus, a bustle of infinite enquiry and research, or even the mere mechanical labour of copying, may be employed, to evade and shuffle off real labour, -- the real labour of thinking.
 They said therefore unto him, "What sign shewest 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.'"
 Then Jesus said 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."
 And Jesus said unto them, "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.
 All that the Father giveth me shall come to me; and him that cometh to me I will in no wise cast out.
Jesus' followers are those who actively come to him -- and yet in the same breath, they are also described as being passively given to him by the Father. Both divine grace and the personal exercise of free will play a role. Choosing to follow Jesus is sufficient; no one who makes that choice will be rejected.
 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."
 Jesus saith unto her, "Thy brother shall rise again." Martha saith unto him, "I know that he shall rise again in the resurrection at the last day." Jesus said unto her, "I am the resurrection, and the life: he that believeth in me, though he were dead, yet shall he live:  And whosoever liveth and believeth in me shall never die. Believest thou this?"
 She saith unto him, "Yea, Lord: I believe that thou art the Christ, the Son of God, which should come into the world."
 The Jews then murmured at him, because he said, "I am the bread which came 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?'"
 Jesus therefore answered and said unto them, "Murmur not among yourselves.
 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.
 Not that any man hath seen the Father, save he which is of God, he hath seen the Father.
 Verily, verily, I say unto you, He that believeth on me hath everlasting life.  I am that bread of life.  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 for ever: and the bread that I will give is my flesh, which I will give for the life of the world." The Jews therefore strove among themselves, saying, "How can this man give us his flesh to eat?" 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.
If you eat and drink Jesus, then Jesus is in you -- but why are you also in Jesus? This has the same paradoxical nature as a couplet attributed to Jesus in the Gospel of Thomas (Saying 7):
Blessed is the lion which a man eats, making the lion human.Cursed is the man which a lion eats, making the lion human.
If a man eats a lion, the lion becomes human, because the matter that had been part of a lion is now part of a man instead. If a lion eats a man, the lion also becomes human, because human matter is now incorporated into the body of the lion.
By the same logic, if you eat Jesus, you are transformed by incorporating Jesus into yourself, and Jesus is transformed by becoming part of you. (Or Jesus could eat you, of course -- but assuming Jesus is the "lion" of the Thomas saying, this Soviet-Russia version of Communion is to be avoided.)
 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 for ever."