How do we reconcile the supplications of the Companions and the Tabi'un for the alteration of destiny, and hadiths such as "Caution does not avert destiny" and "Nothing repels destiny except supplication," with the fact that caution, supplication, and belief in divine decree and destiny are all part of destiny itself?

Everything that occurs is by the decree (Qada') and divine preordainment (Qadar) of Allah, and it is of two types: an unalterable, absolute decree (Qada' Mubram) that does not change, and a suspended decree (Qada' Mu'allaq) recorded in the scrolls of the angels, which can change through supplication (Du'a), charity (Sadaqa), and righteousness (Birr). Thus, supplication, charity, and righteousness are means of repelling affliction and increasing life and provision. This does not contradict Allah's eternal knowledge and what is inscribed in the Preserved Tablet (Al-Lawh Al-Mahfuz).