Rom 15:1

“After giving the doxology then, he again goes from prayer to exhortation, directing his discourse against the stronger, and saying as follows: "We then that are strong, ought"-it is "we ought," not "we are so kind as to." What is it we ought to do?-"to bear the infirmities of the weak." See how he has roused their attention by his praises, not only by calling them powerful, but also by putting them alongside of himself. And not by this only, but by the advantage of the thing he again allures them, and by its not being burdensome. For thou, he says, art powerful, and art no whit the worse for condescending. But to him the hazard is of the last consequence, if he is not borne with. And he does not say the infirm, but the "infirmities of the weak," so drawing him and bending him to mercy. As in another place too he says, "Ye that are spiritual restore such an one." (Gal. vi. I) Art thou become powerful? Render a return to God for making thee so. But render it thou wilt if thou settest the weakness of the sickly right. For we too were weak, but by grace we have become powerful. And this we are to do not in this case only, but also in the case of those who are weak in other respects. As, for instance, if any be passionate, or insolent, or has any such like failing bear with him. And how is this to be? Listen to what comes next. For after saying "we ought to bear," he adds, "and not to please ourselves."”

“After the prayer he again offers exhortation and gratifies the perfect by placing them on the same level as himself and calling them strong. He did not simply say "weaknesses," but "the weaknesses of the powerless," that is, intensifying the expression in order to draw them to greater compassion. Having spoken of our obligation to bear the weaknesses of others, he teaches how to fulfill it. For this, he says, it is necessary that we seek not only our own benefit.”

“The Apostle taught above that the stronger should avoid scandalizing the weak; here he teaches that the stronger should bear with the failings of the weak. In regard to this he does two things: first, he proposes an admonition; second, he clarifies it, at let every one of you. This admonition contains two parts: the first pertains to external behavior. Hence he says: not only should we avoid scandalizing the weak, but we who are stronger in faith ought to bear the infirmities of the weak. For as in a material edifice certain stronger material is selected to support the edifice's entire weight, upon which weaker material is set, as are the foundation and pillars, so in the spiritual edifice of the Church stronger men are not only chosen but made stronger to support the weight of the others. Hence it says in a psalm: I have strengthened its pillars (Ps 75:4) and in Galatians: bear one another's burdens (Gal 6:2). But the stronger support the failings of the weak, when they endure the shortcomings of the weak patiently and, so far as they can, try to help them. The second pertains to the internal intention. Hence it is said: and not to please ourselves, i.e., always desire the fulfillment of what pleases us, but we should condescend to the wills of others, so as to do what pleases them and is useful to them: just as I try to please all men in everything I do (1 Cor 10:33).”