Zechariah 4:13

We have also mentioned before, that the desire of improvement observed in Zechariah ought to be noticed. For though we attain not immediately what God teaches, yet the obscurity of a passage ought not to damp our ardor; but we ought rather to imitate the Prophet, who, in things difficult and unknown to him, asked explanations from the angel. Angels are not indeed sent now to us from heaven to answer our questions; but yet no one shall be without benefit who will humbly and with a sincere desire ask of God; for God will either by his ministers so elucidate what seems obscure to us and full of darkness, that we shall know that there is nothing but what is clear in his word; or he will by the Spirit of knowledge and judgment supply what is deficient in the ministrations of men.

And this is also the reason why the angel replies, Dost thou not know what these mean? For he does not upbraid Zechariah with ignorance, but rather reminds all the faithful, that they ought to quicken themselves, and to exert all their ardor to learn, lest sloth should close up the way against them. This reply, then, of the angel no doubt belongs to us all, “Dost thou not know what these mean?” We ought to remember that the things we esteem as common far exceed our thoughts. It indeed often happens that one runs over many parts of Scripture, and thinks that he reads nothing but what is clear and well known, while yet experience teaches us that we are inflated with too much self-confidence; for we look down, as it were from on high, on that doctrine which ought, on the contrary, to be reverently adored by us. Then let every one of us, being warned by this sentence of the angel, acknowledge that he as yet cleaves to first principles, or, at least, does not comprehend all those things which are necessary to be known; and that therefore progress is to be made to the very end of life: for this is our wisdom, to be learners to the end.