Adam Clarke on Psalms 47:3

He shall subdue the people under us - He shall do again for us what he had done for our forefathers - give us dominion over our enemies, and establish us in our own land. I would rather read this in the past tense, relative to what God did for their fathers in destroying the Canaanites, and giving them the promised land for their possession, and taking the people for his own inheritance. This is also applied to the conversion of the Gentiles who, on the rejection of the Jews, have become his inheritance; and whom he has chosen to inherit all those spiritual blessings typified by the sacrifices and other significant rites and ceremonies of the Jewish Church.