Rav Avira taught (sometimes in the name of Rabbi Ammi, sometimes in the name of Rabbi Assi) that the words "And the child grew, and was weaned ("va-yigamal", ), and Abraham made a great feast on the day that Isaac was weaned" in teach that God will make a great feast for the righteous on the day that God manifests ("yigmol") God's love to Isaac's descendants. After they have eaten and drunk, they will ask Abraham to recite the Grace after meals ("Birkat Hamazon"), but Abraham will answer that he cannot say Grace, because he fathered Ishmael. Then they will ask Isaac to say Grace, but Isaac will answer that he cannot say Grace, because he fathered Esau. Then they will ask Jacob, but Jacob will answer that he cannot, because he married two sisters during both their lifetimes, which was destined to forbid. Then they will ask Moses, but Moses will answer that he cannot, because God did not allow him to enter the Land of Israel either in life or in death. Then they will ask Joshua, but Joshua will answer that he cannot, because he was not privileged to have a son, for reports, "Nun was his son, Joshua was his son," without listing further descendants. Then they will ask David, and he will say Grace, and find it fitting for him to do so, because records David saying, "I will lift up the cup of salvation, and call upon the name of the Lord."