The covenant was to be accomplished in due time. Abram's name became Abraham, meaning father of many nations, while Sarah means mother of nations. The Lord confirmed again the promised Seed and the land that He shall give to Abraham and his descendants as an everlasting covenant (v7). The token of the covenant was circumcision, which Abraham and his seeds must keep. Foreigners and slaves that will accept the Lord as their God must also be circumcised. Here shows that God's grace began to work from Abraham to many families of the earth. This religious observance was required under the severe penalty, and it is dangerous to make light of Divine institution, and to live in the neglect of it. "That persons shall be cut off from his people, he has broken My covenant" (16). Abraham was ninety years old when circumcised, Ishmael was thirteen, and all eight days old among God's people shall be circumcised. The covenant blessing was reserved for Isaac, and appropriated to him. Christians are no longer strangers and outsiders in God's covenant when they accepted Christ as Lord and Savior. God bless.