How does Islam view divine decree and destiny (Al-Qada' wa Al-Qadar)?

Belief in divine decree (Qada') and destiny (Qadar) is one of the fundamentals of faith. It means Allah's comprehensive knowledge of everything, His being the Creator of all things, and that everything that occurs happens by His will and decree. Indeed, everything was written in the Preserved Tablet (Al-Lawh Al-Mahfuz) fifty thousand years before the creation of creation. What was destined to befall a servant could not have missed him, and what was destined to miss him could not have befallen him. The servant has a will befitting his state, but it is subordinate to the will of the Creator.