1 Thessalonians 1:4

"Knowing, brethren beloved of God, your election, how that our Gospel came not unto you in word only, but also in power, and in the Holy Ghost, and in much assurance; even as ye know what manner of men we showed ourselves among you for your sake."

Knowing what? How "we showed ourselves among you"? Here he also touches upon his own good actions, but covertly. For he wishes first to enlarge upon their praises, and what he says is something of this sort. I knew that you were men of great and noble sort, that you were of the Elect. For this reason we also endure all things for your sake. For this, "what manner of men we showed ourselves among you," is the expression of one showing that with much zeal and much vehemence we were ready to give up our lives for your sake; and for this thanks are due not to us, but to you, because ye were elect. On this account also he says elsewhere, "And these things I endure for the Elect's sake." (2 Tim. ii. 10) For what would not one endure for the sake of God's beloved ones? And having spoken of his own part, he all but says, For if you were both beloved and elect, we suffer all things with reason. For not only did his praise of them confirm them, but his reminding them that they too themselves had displayed a fortitude corresponding to their zeal.

He says, we remember you because we know that you are chosen by God: for you have been chosen for the faith preferentially over many others. But how is this evident, holy Paul? Listen, he says, to what follows next.

Then when Paul says, "For we know, brethren beloved by God, that he has chosen you," he recalls their blessings in particular matters. First, he congratulates them for having received the gospel devoutly and willingly in spite of tribulations; secondly, Paul congratulates them because they did not fall away from the gospel in time of trial (2:1). Again, the first part is divided into two. First, Paul points out the kind of preaching that had been given to them; secondly, he points out how this preaching was received by them (1:6). In treating the first point Paul does three things. First, he tells what he knew about them; secondly, he indicates the manner of his preaching (1:5); thirdly, he remarks upon what they knew about the Apostle (1:5).

So Paul says, "brethren, beloved by God," not only generally, insofar as God gives existence to all of nature, but specifically, insofar as you are each called to an eternal reward: "Yet I have loved Jacob" (Mal. 1:3). "All those consecrated to him were in his hand" (Deut. 33:3). "He has chosen you," as if implying: I am certain that you are among the elect, although you did not merit this election; rather you are freely chosen by God. And I know this because God granted me abundant evidence of this in preaching, that is, that those to whom I preach are chosen by God, for God gives them the grace to listen profitably to the word preached to them; or else, God gives me the grace to preach rewardingly to them.