In other words...
In other words, this phrase does not intend to negate the authority of others, but it intends to make this matter clear that it is He Who is Mighty by Essence and is the absolute Owner, and whoever possesses anything he has it from His side. Then the verse implies that if today that the Romans failed and the polytheists became happy, on that day when the Romans overcame the believers would become happy.
The verse continues saying: “…and on that day the believers shall rejoice.” Yes, by Allah’s help they will be happy. The next Holy verse announces: “With the help of Allah, He helps whom He pleases, and He is the Mighty, the Merciful.” Upon the objective meaning of the sentence: “On that day the believers shall rejoice”, the commentators have delivered different ideas. Some of them have said that this…