Dua at the start of the prayer (after takbeer) — context

Meaning of Al-Muqaddim and Al-Mu-akhkhir: Allah puts forward and favours whom He wills from amongst His creation just as He defers and holds back whom He wills in accordance to His wisdom. E.g. Favouring man over the rest of creation, favouring the Prophets over the rest of mankind, favouring Muhammad over all the Prophets and Messengers…etc.