1Thess 3:12

“Suppose we first loved him so as to merit his love in return. Then wouldn't we first choose him so as to merit our being chosen by him? But he who is Truth itself says otherwise and openly contradicts such human vanity by declaring, "You have not chosen me." Consequently, if it is not you who have chosen, then it is certainly not you who have loved; for how could they choose him whom they did not love? "But it is I," he says, "who have chosen you." And how could they possibly fail to choose him afterward or fail to prefer him to all the goods of this world? It was because they were chosen that they chose him. They were not chosen because they had chosen him. There would be no merit in men's choosing him unless the action of God's grace in choosing them had gone before. That is why in imparting his blessing to the Thessalonians the apostle Paul declares, "And may the Lord make you to increase and abound in charity toward one another and toward all men." He who gave this blessing to love one another is the same who gave us the love to love one another.”

“Do you see the irresistible impulse of love in the fact that he prays for them, that the Lord would fill and overfill them with love? And not only toward one another, but toward all. For the love of God is revealed precisely in the fact that it strives to embrace everyone. But if you love one person and not another, then this is human love.”

“The other is for their welfare, so Paul asks: and may the Lord make you increase, that is, in faith: "May the Lord add to his people a hundred times as many as they are" (1 Chr. 21:3). And Paul prays also that their merits may increase; so he says, and abound in love, which can always increase in this life: "Above all these put on love, which binds everything together" (Col. 3:14). And, first, charity to one another, secondly, charity to all men. "Let us do good to all men, and especially to those who are of the household of faith" (Gal. 6:10). And Paul gives an example of himself when he comments: as we do to you, as if to say: just as I also love you: "You are in our hearts, to die together and to live together" (2 Cor. 7:3).”