Observe too, that he says, “The Lord grant him mercy.” For as he himself had obtained mercy from Onesiphorus, so he wished him to obtain the same from God. Moral. And if Onesiphorus, who exposed himself to danger, is saved by mercy, much more are we also saved by the same. For terrible indeed, terrible is that account, and such as needs great love for mankind, that we may not hear that awful sentence, “Depart from me...I never knew you, you that work iniquity”; or that fearful word, “Depart, you cursed, into everlasting fire, prepared for the devil and his angels”: that we may not hear, “Between us and you there is a great gulf fixed”: that we may not hear that voice full of horror, “Take him away, and cast him into outer darkness”: that we may not hear those words full of terror, “Thou wicked and slothful servant.” For awful truly and terrible is that tribunal. And yet God is gracious and merciful. He is called a God “of mercies and a God of comfort”; good as none else is good, and kind, and gentle, and full of pity, Who “wills not the death of a sinner, but that he should be converted and live.” Whence then, whence is that Day so full of agony and anguish? A stream of fire is rolling before His face. The books of our deeds are opened. The day itself is burning as an oven, the angels are flying around, and many furnaces are prepared. How then is He good and merciful, and full of lovingkindness to man? Even herein is He merciful, and He shows in these things the greatness of His lovingkindness. For He holds forth to us these terrors, that being constrained by them, we may be awakened to the desire of the kingdom.
And observe how, besides commending Onesiphorus, he specifies his kindness, “he oft refreshed me”; like a wearied wrestler overcome by heat, he refreshed and strengthened him in his tribulations. And in how many things he ministered to me at Ephesus, you know very well. Not only at Ephesus, but here also he refreshed me. For such ought to be the conduct of one on the watch and awakened to good actions, not to work once, or twice, or thrice, but through the whole of life. For as our body is not fed once for all, and so provided with sustenance for a whole life, but needs also daily food, so in this too, godliness requires to be supported every day by good works. For we ourselves have need of great mercy. It is on account of our sins that God, the Friend of man, does all these things, not that He needs them Himself, but He does all for us. For therefore it is that He has revealed them all, and made them known to us, and not merely told us of them, but given us assurance of them by what He has done. Though He was worthy of credit upon His word only, that no one may think it is said hyperbolically, or in the way of threatening merely, we have further assurance by His works. How? By the punishments which He has inflicted both publicly and privately. And that you may learn by the very examples, at one time he punished Pharaoh, at another time He brought a flood of water upon the earth, and that utter destruction, and again at another time a flood of fire: and even now we see in many instances the wicked suffering vengeance, and punishments, which things are figures of Hell.
For lest we should slumber and be slothful, and forget His word, He awakens our minds by deeds; showing us, even here, courts of justice, judgment seats, and trials. Is there then among men so great a regard for justice, and does God, whose ordinance even these things are, make no account of it? Is this credible? In a house, in a market-place, there is a court of justice. The master daily sits in judgment upon his slaves, calls them to account for their offenses, punishes some and pardons others. In the country, the husbandman and his wife are daily at law. In a ship, the master is judge, and in a camp the general over his soldiers, and everywhere one may see judicial proceedings. In trades, the master judges the learner. In short all, publicly and privately, are judges to one another. In nothing is the consideration of justice overlooked, and all in every place give account of their actions. And is the inquisition for justice here thus spread through cities, through houses, and among individuals; and is there no regard for what is justice there, where “the right hand of God is full of righteousness”, and “His righteousness is as the mountains of God”?
How is it then that God, “the righteous Judge, strong and patient”, bears thus with men, and does not exact punishment? Here you have the cause, He is longsuffering, and thereby would lead you to repentance. But if you continue in sin, thou “after your hardness and impenitent heart treasurest up unto yourself wrath.” If then He is just, He repays according to desert, and does not overlook those who suffer wrongfully, but avenges them. For this is the part of one who is just. If He is powerful, He requites after death, and at the Resurrection: for this belongs to him who is powerful. And if because He is longsuffering He bears with men, let us not be disturbed, nor ask, why He does not prosecute vengeance here? For if this were done, the whole human race before this would have been swept away, if every day He should call us to account for our transgressions, since there is not, there is not indeed, a single day pure from sin, but in something greater or less we offend; so that we should not one of us have arrived at our twentieth year, but for His great long-suffering, and His goodness, that grants us a longer space for repentance, that we may put off our past transgressions.
Source: Homilies on Second Timothy (New Advent)