Revelation 5:9-10 And they sung a new song, saying, Thou art worthy to take the book, and to open the seals thereof: for thou wast slain, and hast redeemed us to God by thy blood out of every kindred, and tongue, and people, and nation;  And hast made us to our God kings and priests: and we shall reign on the earth.

God is now separating the sheep from the goats.  He is separating those who will be led from those who must be driven.  He is calling those He loves from the far corners of the earth to come to be part of His glorious body.  He is saying, "Who will yield?  Who will submit?"  These are the ones He can trust to rule and to reign over the earth.