1 Thessalonians 3:13

13That he may confirm your hearts. He employs the term hearts here to mean conscience, or the innermost part of the soul; for he means that a man is acceptable to God only when he brings holiness of heart; that is, not merely external, but also internal. But it is asked, whether by means of holiness we stand at God’s judgment-seat, for if so, to what purpose is remission of sins? Yet Paul’s words seem to imply this — that their consciences might be irreproveable in holiness. I answer, that Paul does not exclude remission of sins, through which it comes that our holiness, which is otherwise mixed up with many pollutions, bears God’s eye, for faith, by which God is pacified towards us, so as to pardon our faults, (565) precedes everything else, as the foundation comes before the building. Paul, however, does not teach us what or how great the holiness of believers may be, but desires that it may be increased, until it attain its perfection. On this account he says — at the coming of our Lord, meaning that the completion of those things, which the Lord now begins in us, is delayed till that time.

With all his saints. This clause may be explained in two ways, either as meaning that the Thessalonians, with all saints, may have pure hearts at Christ’s coming, or that Christ will come with all his saints. While I adopt this second meaning, in so far as concerns the construction of the words, I have at the same time no doubt that Paul employed the term saints for the purpose of admonishing us that we are called by Christ for this end—that we may be gathered with all his saints. For this consideration ought to whet our desire for holiness.