And therefore, Avraham is called 'Yedid' (beloved), because he was faithful with Hashem his God, as it is written (Nehemiah 9:8), "and You found his heart faithful before You." Similarly, Yitzchak is called Yedid (see the commentary of the Rosh on Bereshit 17:13 and the Baal Haturim there, 21), as we say in the blessing of the Brit Milah: 'Who sanctified the beloved one from the womb,' because he sacrificed himself on the altar.