World Wide Study Bible
a Bible passage
17so that everyone who belongs to God may be proficient, equipped for every good work.
17 That the man of God may be perfect. Perfect means here a blameless person, one in whom there is nothing defective; for he asserts absolutely, that the Scripture is sufficient for perfection. Accordingly, he who is not satisfied with Scripture desires to be wiser than is either proper or desirable.
But here an objection arises. Seeing that Paul speaks of the Scriptures, which is the name given to the Old Testament, how does he say that it makes a man thoroughly perfect? for, if it be so, what was afterwards added by the apostles may be thought superfluous. I reply, so far as relates to the substance, nothing has been added; for the writings of the apostles contain nothing else than a simple and natural explanation of the Law and the Prophets, together with a manifestation of the things expressed in them. This eulogium, therefore, is not inappropriately bestowed on the Scriptures by Paul; and, seeing that its instruction is now rendered more full and clear by the addition of the Gospel, what can be said but that we ought assuredly to hope that the usefulness, of which Paul speaks, will be much more displayed, if we are willing to make trial and receive it?