Dear Dr. Shabbir,
i would like to quote the Japanese Book, Hagakure- The Way of A Samurai which in the beginning states thus:
"The Way of the Samurai is found in death. When it comes to either/or, there is only the quick choice of death. It is not particularly difficult. Be determined and advanced. To say that dying without reaching one's aim is to die a dog's death is the frivolous way of sophisticates. WHEN PRESSED WITH THE CHOICE OF LIFE OR DEATH, IT IS NOT NECESSARY TO GAIN ONE'S AIM.
We all want to live. And in large part we make our logic according to what we like. But not having attained our aim and continuing to live is cowardice. This is a thin dangerous line. To die without gaining one’s aim is a dog’s death and fanaticism. But there is no shame in this. This is the substance of the Way of the Samurai. If by setting one’s heart right every morning and evening, one is able to live as though his body were already dead, he pains freedom in the Way. His whole life will be without blame, and he will succeed in his calling."
According to the Qur'an the results of our life and actions rests only with God. We usually judge ourselves and our situations by some standards. When we take our thoughts and desires and other human authorities as our sources of guidance and masters, then we would easily fall in despair and lose our strength and hope. In the light of the Qur'an no human being is allowed to commit suicide. We need to overcome our weakness and find strength and courage in the light of Divine Revelation.
39:53 Convey to them, "O You servants of Mine who have so far wasted yourselves! Do not despair of the mercy of God. God absolves your imperfections and protects you from the detriment of all that caused you to trail behind in humanity – For, He is the Forgiving, the Merciful."
According to my limited knowledge, when a Samurai commits suicide that's because he's serving his master and that he's so much devoted to his master that he would lay his life for the sake of his master- he would easily commit suicide if his master orders him so- and this is a beautiful choice (without considering the Qur'an). But since we have the Qur'an among us, such courage and determination must be devoted to our Real Master, Sustainer and Lord.
13:36 So, those to whom We have given the Book, rejoice in what is revealed to you (O Prophet!). But, among the (dissenting) groups, there are those who deny a part of it. Say, “I am commanded only that I serve God and associate none with Him. Unto Him I invite all mankind, and HE IS MY GOAL.”