Musannaf Ibn Abi Shaybah

Hazrat Abu Shurayh Khuza'i narrates that the Messenger of Allah, peace and blessings be upon him, said: If a person is killed or wounded, then he has a choice among three things. If he intends a fourth thing, then restrain his hand. These actions are: to kill (in retaliation), to forgive, or to accept blood money. Whoever chooses one of these and then returns (to seek revenge again), for him is the fire of Hell, in which he will abide forever.