Not only is suicide a sin, it is the sin. It is the ultimate and absolute evil, the refusal to take an interest in existence; the refusal to take the oath of loyalty to life.
The man who kills a man, kills a man. The man who kills himself, kills all men; as far as he is concerned he wipes out the world. His act is worse (symbolically considered) than any rape or dynamite outrage. For it destroys all buildings: it insults all women. The thief is satisfied with diamonds; but the suicide is not: that is his crime. He cannot be bribed, even by the blazing stones of the Celestial City. The thief compliments the things he steals, if not the owner of them. But the suicide insults everything on earth by not stealing it. He defiles every flower by refusing to live for its sake. There is not a tiny creature in the cosmos at whom his death is not a sneer. When a man hangs himself on a tree, the leaves might fall off in anger and the birds fly away in fury: for each has received a personal affront. Of course there may be pathetic emotional excuses for the act. There often are for rape, and there almost always are for dynamite. But if it comes to clear ideas and the intelligent meaning of things, then there is much more rational and philosophic truth in the burial at the cross-roads and the stake driven through the body, than in Mr. Archer’s suicidal automatic machines. There is a meaning in burying the suicide apart. The man’s crime is different from other crimes — for it makes even crimes impossible.
–GK Chesteron, Orthodoxy
These may seem harsh words to quote in the wake of Robin Williams’ suicide. They seem, I am sure, harsh in the wake of any man’s suicide, whether of an actor loved the nation over or of an unknown family man leaving behind only a wife and some children. They also represent, to some extent, the orthodox opinion of not only the Church since her founding, but of western man, from the Stoics like Seneca to the Greeks’ Socrates.
They also are the sort of thing which sound inflammatory to the ears of those who mourn. My intent in quoting Mr. Chesterton is not to pour gasoline on the metaphorical flames in the wake of Mr. Williams’ unfortunate demise. That suicide is a damnable sin does not ensure that all who commit it will be damned, nor is the darkest depression equal to that unforgivable sin which is despair. The two are easily confused, and the former may be a symptom of the latter.
Yet there is a crucial difference between these two. Depression may eat at the mind and at the soul, but it is not in itself a sin. Depression may tempt to despair, but it is not despair. A depressed man may at times see his situation as hopeless, but he has not necessarily renounced hope.
A suicidal man may have lost his will to live, may mistake life for suffering—and may see in death a hope for new life . He may be mistaken in his methods, and he may be said to be wrong for his final act. He may have misplaced his hope, a statement which is in a sense true of any sin.
Hope—this is what every man needs, whether he is suffering at this moment or not. Hope is that virtue which leads from faith to love, and which bridges from here to hereafter. Writing about hope, the philosopher Josef Pieper notes that “Man is true to himself only when he is stretching forth–in hope — toward a fulfillment that cannot be reached in [this life].”
We all suffer to some extent in this life; we all suffer uniquely and individually—and yet in a sense we all suffer together. Do we act in hope in our suffering, and thus find joy even in times of sorrow, or do we wallow in self-pity and sink through misery and to despair? Do we notice the suffering of others, or remain focused only upon our own? Suffering creates responsibility, and we may learn to bear our own suffering by helping others to bear theirs—that is, by showing mercy.
Mercy springs from sorrow at another’s suffering, and our practice of it leads to our being granted it in the end. The simplest act of mercy, and the one which is perhaps most obviously rooted in hope, is to pray for the living and for the dead.
We might begin by asking God’s mercy for the living and the dead, and we might end with thanksgiving for the mercy He has shown thus far, not least of which is the greatest mercy of all, which comes from Christ’s suffering and which leads to our salvation.
Gratitude is the ultimate antidote to depression, and if gratitude persists in the face of depression it may yet allow joy to comingle with tears. That is, alas, the best we might look forward too in this vale of tears, but hope looks forward to that which is to come in the next life.
Thus, we must pray not only for others, but again for ourselves as well, not only for the dead but also for the living. Here our prayer might be that of Blessed John Henry Cardinal Newman:
“May [God] support us all the day long, til the shades lengthen, and evening comes, and the busy world is hushed, and the fever of life is over, and our work is done! Then in his mercy may he give us a safe lodging, and a holy rest, and peace at last” (Sermons Bearing on Subjects of the Day).
 In choosing to take his own life, the man who commits suicide commits a sin, materially. But formally? Formally, he may be forgiven. God is merciful, especially to those whom seek mercy.