"“You ought,” he says, “to have been the instructors of others, but ye are not even disciples capable of comprehending an ordinary truth; for ye do not as yet understand the first rudiments of Christianity.” That he might, however, make them the 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 through life; for he alone is truly wise who owns 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...

but we ought, on the contrary, so to exert ourselves, that our progress may correspond tothe time allowed us.

Doubtless, not only years, but days also, must be accounted for; so that every one ought to strive to make progress; but few there are who summon themselves to an account as to 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."

Calvin on Hebrews 5:12