Genesis 17:21

“But my covenant will one establish with Isaac, etc.] The covenant of circumcision; for though Ishmael was circumcised, and his posterity practised that rite, yet it was not enjoined them of God; nor was it to them, or served the same purpose as to the Israelites; and particularly the promise of the land of Canaan, made in that covenant, belonged only to the posterity of Isaac, and to those only in the line of Jacob, and especially that of the Messiah springing from him, which circumcision had a respect unto: whom Sarah shall bear unto thee, at this set time, in the next year: that is, at the end of nine months, which is the set time a woman goes with child.”

“- The Sealing of the Covenant 1. שׁדי shaday, Shaddai, “Irresistible, able to destroy, and by inference to make, Almighty.” שׁדד shādad “be strong, destroy.” This name is found six times in Genesis, and thirty-one times in Job. 5. אברהם 'abrâhām, Abraham, from אברם 'abrām “high-father,” and הם hām the radical part of המין hāmôn a “multitude,” is obtained by a euphonic abbreviation אברהם 'abrâhām, “father of a multitude.” The root רהם rhm is a variation of רום rvm; affording, however, a link of connection in sound and sense with the root המה hāmâh “hum, be tumultuous,” from which comes המון hāmôn a “multitude.” The confluence of the biliterals רם rm and הם hm yields the…”