The Lord God had told his Old Testament people that they were to give the first of the crop to God (whether grain from the field or lamb from the flock or even your own baby; Exodus 13:2; Exodus 22:29–30; Exodus 23:19; Exodus 34:19–20). The idea was that every Israelite was to acknowledge that everything he possessed actually belonged to the Lord and so was to be used for the Lord’s glory. By giving the first of the crop, the pious Israelite pledged that he would use the entirety of the crop for the Lord’s service. That the 144,000 redeemed from mankind were “firstfruits for God and the Lamb” indicated that the entirety of earth’s population actually belonged to God and would in some way serve to advance his kingdom. That includes those who willingly bowed to the dragon and his beasts.
4 It is these who have not defiled themselves with women, for they are virgins. It is these who follow the Lamb wherever he goes. These have been redeemed from mankind as firstfruits for God and the Lamb,