It is not rightful for a Muslim to kill another Muslim, unless it occurs by mistake; and the one who mistakenly kills a Muslim must set free a Muslim slave and pay blood-money to the family of the slain, except if they forego it; and if the victim is of a people who are hostile to you, and the killer is a Muslim, then only the setting free of a Muslim slave (is obligatory); and if the victim is from a people between whom and you there is a treaty, then blood-money must be paid to his family and the setting free of a Muslim slave; therefore one who has no means must fast for two consecutive months; this is his penance before Allah; and Allah is All Knowing, Wise. 92 And whoever kills a believer intentionally, his punishment is hell; he shall abide in it, and Allah will send His wrath on him and curse him and prepare for him a painful chastisement. 93 [Hence,] O you who have attained to faith, when you go forth [to war] in God's cause, use your discernment, and do not - out of a desire for the fleeting gains of this worldly life - say unto anyone who offers you the greeting of peace, "Thou art not a believer" for with God there are gains abundant. You, too, were once in the same condition - but God has been gracious unto you. Use, therefore, your discernment: verily, God is always aware of what you do. 94 The holders back from among the believers, not having any injury, and those who strive hard in Allah's way with their property and their persons are not equal; Allah has made the strivers with their property and their persons to excel the holders back a (high) degree, and to each (class) Allah has promised good; and Allah shall grant to the strivers above the holders back a mighty reward: 95 [many] degrees thereof and forgiveness of sins, and His grace; for God is indeed much-forgiving, a dispenser of grace. 96