3 Jesus answered him, "Very truly, I tell you, no one can see the kingdom of God without being born from above." 4 Nicodemus said to him, "How can anyone be born after having grown old? Can one enter a second time into the mother's womb and be born?"
Matthew Henry's Commentary on John 3:3-4
Commentary on John 3:1-21
(Read John 3:1-21)
Nicodemus was afraid, or ashamed to be seen with Christ, therefore came in the night. When religion is out of fashion, there are many Nicodemites. But though he came by night, Jesus bid him welcome, and hereby taught us to encourage good beginnings, although weak. And though now he came by night, yet afterward he owned Christ publicly. He did not talk with Christ about state affairs, though he was a ruler, but about the concerns of his own soul and its salvation, and went at once to them. Our Saviour spoke of the necessity and nature of regeneration or the new birth, and at once directed Nicodemus to the source of holiness of the heart. Birth is the beginning of life; to be born again, is to begin to live anew, as those who have lived much amiss, or to little purpose. We must have a new nature, new principles, new affections, new aims. By our first birth we were corrupt, shapen in sin; therefore we must be made new creatures. No stronger expression could have been chosen to signify a great and most remarkable change of state and character. We must be entirely different from what we were before, as that which begins to be at any time, is not, and cannot be the same with that which was before. This new birth is from heaven, Numbers 21:6-9. In this observe the deadly and destructive nature of sin. Ask awakened consciences, ask damned sinners, they will tell you, that how charming soever the allurements of sin may be, at the last it bites like a serpent. See the powerful remedy against this fatal malady. Christ is plainly set forth to us in the gospel. He whom we offended is our Peace, and the way of applying for a cure is by believing. If any so far slight either their disease by sin, or the method of cure by Christ, as not to receive Christ upon his own terms, their ruin is upon their own heads. He has said, Look and be saved, look and live; lift up the eyes of your faith to Christ crucified. And until we have grace to do this, we shall not be cured, but still are wounded with the stings of Satan, and in a dying state. Jesus Christ came to save us by pardoning us, that we might not die by the sentence of the law. Here is gospel, good news indeed. Here is God's love in giving his Son for the world. God so loved the world; so really, so richly. Behold and wonder, that the great God should love such a worthless world! Here, also, is the great gospel duty, to believe in Jesus Christ. God having given him to be our Prophet, Priest, and King, we must give up ourselves to be ruled, and taught, and saved by him. And here is the great gospel benefit, that whoever believes in Christ, shall not perish, but shall have everlasting life. God was in Christ reconciling the world to himself, and so saving it. It could not be saved, but through him; there is no salvation in any other. From all this is shown the happiness of true believers; he that believeth in Christ is not condemned. Though he has been a great sinner, yet he is not dealt with according to what his sins deserve. How great is the sin of unbelievers! God sent One to save us, that was dearest to himself; and shall he not be dearest to us? How great is the misery of unbelievers! they are condemned already; which speaks a certain condemnation; a present condemnation. The wrath of God now fastens upon them; and their own hearts condemn them. There is also a condemnation grounded on their former guilt; they are open to the law for all their sins; because they are not by faith interested in the gospel pardon. Unbelief is a sin against the remedy. It springs from the enmity of the heart of man to God, from love of sin in some form. Read also the doom of those that would not know Christ. Sinful works are works of darkness. The wicked world keep as far from this light as they can, lest their deeds should be reproved. Christ is hated, because sin is loved. If they had not hated saving knowledge, they would not sit down contentedly in condemning ignorance. On the other hand, renewed hearts bid this light welcome. A good man acts truly and sincerely in all he does. He desires to know what the will of God is, and to do it, though against his own worldly interest. A change in his whole character and conduct has taken place. The love of God is shed abroad in his heart by the Holy Ghost, and is become the commanding principle of his actions. So long as he continues under a load of unforgiven guilt, there can be little else than slavish fear of God; but when his doubts are done away, when he sees the righteous ground whereon this forgiveness is built, he rests on it as his own, and is united to God by unfeigned love. Our works are good when the will of God is the rule of them, and the glory of God the end of them; when they are done in his strength, and for his sake; to him, and not to men. Regeneration, or the new birth, is a subject to which the world is very averse; it is, however, the grand concern, in comparison with which every thing else is but trifling. What does it signify though we have food to eat in plenty, and variety of raiment to put on, if we are not born again? if after a few mornings and evenings spent in unthinking mirth, carnal pleasure, and riot, we die in our sins, and lie down in sorrow? What does it signify though we are well able to act our parts in life, in every other respect, if at last we hear from the Supreme Judge, "Depart from me, I know you not, ye workers of iniquity?"