9 But, says some one, “We have no fear of dying by violence, but of dying unjustly; and of being punished in a similar way with the guilty—we who have had nothing to do with the crimes of which we are suspected.” What do you say, tell me? Are you afraid of dying unjustly, and would you wish to die justly. But who is there so wretched and miserable, that when he had the alternative of dying unjustly, would rather depart by an act of justice? For if it be necessary to fear death, it is necessary to fear it when it comes upon us justly; since he indeed who dies unjustly, is by this very means made a partaker with all the saints.
For many of those who were approved and distinguished by God, have been subjected to an unjust end; and first of all Abel. For it was not that he had sinned against his brother, or done Cain any harm; but inasmuch as he had honoured God, therefore was he slaughtered. But God permitted it. Was it, think you, because He loved him, or because He hated him? Most clearly, because He loved him, and wished to make his crown the brighter, by that most unjust murder. Do you see then, that it becomes us not to be afraid of dying by violence; nor yet of dying unjustly; but of dying in a state of sin?
Abel died unjustly. Cain lived, groaning and trembling! Which then, I would ask, was the more blessed of the two; he who went to rest in righteousness, or he who lived in sin; he who died unjustly, or he who was justly punished? Would you have me declare unto your Charity, whence it is that we are afraid of death? The love of the kingdom has not penetrated us, nor the desire of things to come inflamed us: otherwise we should despise all present things, even as the blessed Paul did.
Add to this, on the other hand, that we do not stand in awe of hell; therefore death is terrible. We are not sensible of the unsufferable nature of the punishment there; therefore, instead of sin, we fear death; since if the fear of the one held possession of our souls, the fear of the other would not be able to enter.
Source: Homilies on the Statues (New Advent)