1:12-14 Though, as a sinner, the apostle could only rejoice and glory in Christ Jesus, yet, as a believer, he might rejoice and glory in being really what he professed. Conscience witnesses concerning the steady course and tenor of the life. Thereby we may judge ourselves, and not by this or by that single act. Our conversation will be well ordered, when we live and act under such a gracious principle in the heart. Having this, we may leave our characters in the Lord's hands, but using proper means to clear them, when the credit of the gospel, or our usefulness, calls for it.
12. For—reason why he may confidently look for their prayers for him.
our rejoicing—Greek, "our glorying." Not that he glories in the testimony of his conscience, as something to boast of; nay, this testimony is itself the thing in which his glorying consists.
in simplicity—Most of the oldest manuscripts read, "in holiness." English Version reading is perhaps a gloss from Eph 6:5 [Alford]. Some of the oldest manuscripts and versions, however, support it.
godly sincerity—literally, "sincerity of God"; that is, sincerity as in the presence of God (1Co 5:8). We glory in this in spite of all our adversities. Sincerity in Greek implies the non-admixture of any foreign element. He had no sinister or selfish aims (as some insinuated) in failing to visit them as he had promised: such aims belonged to his adversaries, not to him (2Co 2:17). "Fleshly wisdom" suggests tortuous and insincere courses; but the "grace of God," which influenced him by God's gifts (Ro 12:3; 15:15), suggests holy straightforwardness and sincere faithfulness to promises (2Co 1:17-20), even as God is faithful to His promises. The prudence which subserves selfish interests, or employs unchristian means, or relies on human means more than on the Divine Spirit, is "fleshly wisdom."
in the world—even in relation to the world at large, which is full of disingenuousness.
more abundantly to you-ward—(2Co 2:4). His greater love to them would lead him to manifest, especially to them, proofs of his sincerity, which his less close connection with the world did not admit of his exhibiting towards it.