R. Yehudah b. Betheira says: It is written (Exodus 6:9) "And they would not hearken to Moses (as to G–d's delivering them), for shortness of spirit, etc." Now is there anyone who is given glad tidings and does not rejoice? (viz. (Jeremiah 20:1)4) "A son has been born to you—Rejoice him!" His Master is freeing him from bondage and he does not rejoice? What, then, is the intent of "And they would not hearken to Moses, etc."? It was difficult for them to abandon their idolatry, viz. (Ezekiel 20:7) "And I said to them (in Egypt): Let every man cast away the detestations of his eyes and not defile himself with the idols of Egypt." This is the intent of (Exodus 6:13) "And the L–rd spoke to Moses and to Aaron, and He charged them to the children of Israel. He charged them to abandon idolatry.