Thereupon Moses invited the elders to go to Pharaoh with him, but they lacked the courage to appear before the king. Though they started out with Moses, they dropped off stealthily on the way, one by one, and when Moses and Aaron stood in the presence of the king, they found themselves alone, deserted by all the others. The elders did not go out free. Their punishment was that God did not permit them to ascend the holy mountain with Moses. They durst accompany him on the way to God only as far as they had accompanied him on the way to Pharaoh, and then they had to tarry until he came again.
Pharaoh — Moses and Divine Judgment
Legends of the Jews 4:238