Ramban
Jewish
1194–1270
“BEHOLD, MY COVENANT IS WITH THEE, AND THOU SHALT BE THE FATHER OF A MULTITUDE OF NATIONS. This refers to the covenant of the circumcision, as He will explain, “This is the sign of the Covenant,. and after the covenant you will be the father of a multitude of nations.” Blessed be the Lord! By Him alone are actions weighed, for He preceded and commanded Abraham to enter into His covenant to be circumcised before Sarah became pregnant so that his seed would be holy.”