2 For, brethren, you heard just now when the Gospel was read, at least if you had for it the ear not only of the body but also of the heart. What said it? “Take heed that you do not your righteousness before men, to be seen of them.” Did He mean to say this, that whatever good things we do, we should hide them from the eyes of men, and fear to be seen? If you fear spectators you will not have imitators: you ought therefore to be seen. But you must not do it to the end you may be seen.
Not there should be the end of your joy, not there the goal of your rejoicing, that you should account yourself to have gotten the whole fruit of your good work, when you are seen and praised. This is nothing. Despise yourself when you are praised, let Him be praised in you who works by you. Therefore do not for your own praise work the good you do, but to the praise of Him from whom you have the power to do good. From your self you have the ill doing, from God you have the well doing.
On the other hand, see perverse men, how preposterous they are. What they do well, they will needs ascribe to themselves; if they do ill, they will needs accuse God. Reverse this distorted and preposterous proceeding, which puts the thing, as one may say, head downwards, which makes that undermost which is uppermost, and that upwards which is downwards. Do you want to make God undermost and yourself uppermost? You go headlong, not elevatest yourself; for He is always above. What then?
You well, and God ill? Nay rather, say this, if you would speak more truly, I ill, He well; and what I do well from Him is the well-doing: for from myself whatever I do is ill. This confession strengthens the heart, and makes a firm foundation of love. For if we ought to hide our good works lest they be seen of men, what becomes of that sentence of the Lord in the sermon which He delivered on the mount? Where He said this, there He also said a little before, “Let your good works shine before men.” And He did not stop there, did not there make an end, but added, “And glorify your Father which is in Heaven.”
And what says the apostle? “And I was unknown by face unto the Churches of Judea which were in Christ: but they heard only, That he which persecuted us in times past, now preaches the faith which once he destroyed. And in me they glorified God.” See how he also, in regard that he became so widely known did not set the good in his own praise, but in the praise of God. And as for him, in his own person, that he was one who laid waste the Church, a persecutor, envious, malignant, it is himself that confesses this, not we that reproach him therewith.
Paul loves to have his sins spoken of by us, that He may be glorified who healed such a disease. For it was the hand of the Physician that cut and healed the greatness of the sore. That voice from heaven prostrated the persecutor, and raised up the preacher; killed Saul, and quickened Paul. For Saul was the persecutor of a holy man; thence had this man his name, when he persecuted the Christians: afterward of Saul he became Paul. What does the name Paulus mean? Little.
Therefore when he was Saul, he was proud, lifted up; when he was Paul, he was lowly, little. Thus we say, I will see you “paulo post,” i.e. after a little while. Hear that he was made little: “For I am the least of the apostles; and, To me the least of all saints,” he says in another place. So was he among the apostles as the hem of the garment: but the Church of the Gentiles touched it, as did the woman which had the flux, and was made whole.
Source: Homilies on the First Epistle of John (New Advent)