'The Qur’an states in numerous places that the two conditions to live a good life in this world and enter paradise in the Hereafter are: 1) To believe and 2) To perform good deeds.
Belief in Islam consists of a number of elements: belief in God, His angels, His sacred revelations, His Messengers (Prophets) and the Hereafter.
The good deeds are many. Paramount among them are: the performance of prayers, giving the poor dues, being kind to parents, helping next of kin, reconciliation between people, removal of harm from the path of others, etc. One distinct good deed is the Jihad (striving or struggling to do the best). Jihad has two main components: the struggle against the militant enemies of the faith (the lesser Jihad) and the struggle against the demons of self (the greater Jihad).
It is quite well known from the Islamic culture that to “die in the way of God”, i.e. defending the faith and repelling aggressors is one good deed which is highly commended and is considered one of the means to obtain God’s approval and hence an entry to paradise. According to the Qur’an, death in battle against the enemies of the faith is rewarded with paradise: “God has bought from the believers themselves and their possessions in exchange for paradise, that they fight in the way of God and therefore they may kill and get killed. This has been a true promise by Him given in the Torah, the Gospel and the Qur’an, and who is more fulfilling of his promise than God? So rejoice in your transaction (with God) and this is verily the greatest of success” (111, 9). Another verse in the Qur’an that has the same meaning is the following: “O’ you who believe! Do you want me to guide you to a trade that will save you from a painful torment? Believe in God and his Prophet and struggle in the way of God with your possessions and yourselves, this is better for you if you only know. He will forgive your sins and make you enter gardens under which flow rivers, and desirable domiciles in the Gardens of Eden. This is indeed the greatest achievement.” (10-12, 61)
There are a number of other verses in the Qur’an that confirm what has been mentioned in these two quotes. However, it is significant to mention here the existence of other verses in the Qur’an, which condemn in the strongest terms the act of suicide:
“And do not kill yourselves, God is merciful with you. And whosoever does that (kills self) with aggression and inequity, we will make them suffer in Hell fire, and this is easy for God to do” (29-30, 4). In fact there are numerous verses in the Qur’an that prohibits killing any innocent creature. The clearest example is given below: “He who kills a person without (the latter) having killed another person, it is as if he has killed all of humanity, and he who makes one person survive, it is as if he has caused all humanity to survive” (32,5)
To summarize, the Qur’an and the tradition of the Prophet of Islam leave no doubt that basically human life is sacrosanct and should never be terminated except for strong reasons that are essential for maintaining justice, social peace and collective survival. The Qur’an has also very strong words for those who reject the faith of other Muslims and consider them apostates or non-believers for flimsy reasons: “He who deliberately kills a believer, then his domicile will be in Hell fire for eternity, and God will be angry with him and will curse him by preparing for him a great punishment” (93-4).'
--Muhaf Yassiri, What Is Happening in Iraq?