Tafsir of Al-Fath 48:22

And if those who disbelieve fight against you, they certainly would have turned their backs; then they would have found neither a protector nor a helper. Allah the Exalted and Most Honored delivers the glad tidings to His believing servants that had the idolators fought them, Allah would have given victory to His Messenger and His faithful servants. Then, the army of the disbelievers would have been defeated and would have deserted the battlefield and fled. They would not have found any helper or supporter, because they were fighting Allah, His Messenger and His Faithful Party. Allah the Exalted and Most Honored said,

سنة الله التي قد خلت من قبل ولن تجد لسنة الله تبديﻼ