Every event in the eternal past was predetermined by Allah. A man is also bound by a destiny ordained for him. The Prophet Muhammad (saas) told his people that they would not encounter anything other than what was predestined for them, for which reason they need to trust in Allah moment by moment and earn the rewards of such an attitude:

Say: “Nothing can happen to us except what Allah has ordained for us. He is our Guardian. It is in Allah that the believers should put their trust.” (Surat at-Tawba, 51)

The Prophet (saas), by his submission to Allah, was an example to all Muslims, and he warned people that they would never have the power to change anything that came from Allah:

"Everything is by decree—even incapacity and ability.” (Malik’s Muwatta)

“… When you ask for anything ask it from Allah, and if you seek help seek it from Allah. Know that if the people were to unite to do you some benefit, they could benefit you only with what Allah had recorded for you, and that if they were to unite to do you some injury, they could injure you only with what Allah had recorded for you. The pens are withdrawn and the pages are dry.”(Tirmidhi)