Genesis 17:15

“And God said unto Abraham, etc.] After he had changed his name, and given him the covenant of circumcision: as for Sarai thy wife, thou shalt not call her name Sarai, but Sarah her name [shall be]; her former name Sarai signifies “my princess”, or rather “princesses”, being to him in the room of many, and better than ten thousand; yet only a princess to him, and in his family, being sole mistress there: but Sarah signifies, as Jarchi observes, “princess” absolutely, because she was princess over all the princes and people that should come of her, as well as be the mother and princess of all female believers, who are called her daughters, (<600306>1 Peter 3:6).”

“As for Sarai . . . I will . . . give thee a son also of her--God's purposes are gradually made known. A son had been long ago promised to Abraham. Now, at length, for the first time he is informed that it was to be a child of Sarai.”

“- 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…”

“17:15-16 Sarah: The new name, fitting for one who would be the mother of kings, was a milestone in Sarah’s calling and brought attention to the promise.”