The Brachos

Why would Yitzchak want to give the brachos to Esav when he knew Yaakov stood higher? And how could Esav, so deep in this world, believe he had a share in Olam HaBa too? Rav Moshe Feinstein reads the second explanation of Rashi on the twins fighting in the womb and finds one mistaken assumption sitting behind both questions. It is an assumption any of us can slip into without noticing, in the middle of our own avodas Hashem.