Jabir bin 'Abdullah narrated that the Messenger of Allah (s.a.w) said: 'A slave (of Allah) shall not believe until he believes in Al-Qadar, its good and its bad, such that he knows that what struck him would not have missed him, and that what missed him would not have struck him.
Ali narrated that the Messenger of Allah (s.a.w) said: 'A slave (of Allah) shall not believe until he believes in four: The testimony of La Ilaha Illallah, and that I am the Messenger of Allah whom He sent with the Truth, and he believes in the death, and he believes in the Resurrection after death, and he believes in Al-Qadar.