John Calvin Commentary Hebrews 5:12

"For when by reason of the time ye ought to be teachers, ye have need again that some one teach you the rudiments of the first principles of the oracles of God; and are become such as have need of milk, and not of solid food." — Hebrews 5:12 (ASV)

For when for the time ye ought, etc. This reproof contains very sharp goads to rouse the Jews from their sloth. He says that it was unreasonable and disgraceful that they should still continue in the elements, in the first rudiments of knowledge, when they ought to have been teachers.

“You ought,” he says, “to have been the instructors of others, but you are not even disciples capable of comprehending an ordinary truth; for you do not yet understand the first rudiments of Christianity.” That he might, however, make them more ashamed of themselves, he mentions the “first principles,” or the elements of the beginning of God’s words, as though he had said, You do not know the alphabet.

We must, indeed, learn throughout life, for only he is truly wise who acknowledges that he is very far from perfect knowledge. But we ought still to profit so much by learning as not to continue always in the first principles. Nor are we to act in such a way that what is said by Isaiah should be verified in us, “There shall be to you a precept on precept, a precept on precept,” etc. (Isaiah 28:10); but we ought, on the contrary, so to exert ourselves, that our progress may correspond to the time allowed us.

Doubtless, not only years, but days also, must be accounted for, so that everyone ought to strive to make progress. But few there are who summon themselves to account for past time, or who show any concern for the future.

We are, therefore, justly punished for our sloth, for most of us remain in elements fitted for children. We are further reminded that it is the duty of everyone to impart the knowledge he has to his brothers, so that no one is to retain what he knows to himself, but to communicate it for the edification of others.

Such as have need of milk. Paul uses the same metaphor in 1 Corinthians 3:2; and he reproaches the Corinthians with the same fault that is mentioned here, at least with one that is very similar, for he says that they were carnal and could not bear solid food. Milk then means an elementary doctrine suitable to the ignorant.

Peter takes the word in another sense, when he urges us to desire the milk that is without deceit (1 Peter 2:2), for there is a twofold childhood: that is, concerning wickedness and concerning understanding. And so Paul tells us, “Be not children in understanding, but in wickedness” (1 Corinthians 14:20). They then who are so tender that they cannot receive the higher doctrine are by way of reproach called children.

For the right application of doctrines is to join us together, so that we may grow to a perfect manhood, to the measure of full age, and that we should not be like children, tossed here and there, and carried about by every wind of doctrine (Ephesians 4:14). We must indeed show some indulgence to those who have not yet known much of Christ, if they are not yet capable of receiving solid food. But he who has had time to grow, if he still continues a child, is not entitled to any excuse.

We indeed see that Isaiah brands the reprobate with this mark: that they were like children newly weaned from the breasts (Isaiah 28:9). The doctrine of Christ does indeed minister milk to infants as well as strong meat to adults. But as the infant is nourished by the milk of its nurse, not that it may always depend on the breast, but that it may gradually grow and take stronger food, so also at first we must suck milk from Scripture, so that we may afterwards feed on its bread.

The Apostle, however, so distinguishes between milk and strong food that he still understands sound doctrine by both; but the ignorant begin with the one, and they who are well-taught are strengthened by the other.