Rabbi Aha said in the name of Rabbi Samuel ben Nahman (or others say Rabbi Alexandri's name) in Rabbi Nathan's name that Abraham knew (and observed) even the laws of the courtyard eruv. Rabbi Phinehas (and others say Rabbi Helkiah and Rabbi Simon) said in the name of Rabbi Samuel that Abraham knew even the new name that God will one day give to Jerusalem, as says, "At that time they shall call Jerusalem 'The Throne of God.'" Rabbi Berekiah, Rabbi Hiyya, and the Rabbis of Babylonia taught in Rabbi Judah's name that a day does not pass in which God does not teach a new law in the heavenly Court. For as says, "Hear attentively the noise of His voice, and the meditation that goes out of His mouth." And meditation refers to nothing but Torah, as says, "You shall meditate therein day and night." And Abraham knew them all.