I say not these things as wishing to frighten you, nor to lay a burden on your souls, but to make them wise, and render them easier. I could wish also myself that there were no punishment— yes, myself most of all men. And why so? Because while each of you fears for his own soul, I have to answer for this office also in which I preside over you. So that most of all it is impossible for me to escape. But it cannot be that there is not punishment and a hell. What can I do? Where then, they say, is the kindness of God to men? In many places. But on this subject I will rather discourse at some other season, that we may not confuse the discourses concerning hell. In the meantime let not that slip, which we have gained. For it is no small advantage to be persuaded concerning hell. For the recollection of such discourses, like some bitter medicine, will be able to clear off every vice, if it be constantly settled in your mind. Let us therefore use it, that having a pure heart, we may so be thought worthy to see those things, which eye has not seen, nor ear heard, nor have entered into the heart of man. Which may we all obtain by the grace and mercy of our Lord Jesus Christ, with whom, etc.
Source: Homilies on First Thessalonians (New Advent)