Exodus 17:11

And when Moses lifted up his hands. Here Moses was a figure of Christ on the cross, by whose power and mediation we overcome our spiritual enemies. (Challoner) --- Hands, forming the sign of the cross, as the fathers observe, in the posture of a suppliant. St. Jerome says, the people fasted also till the evening. (contra Jos. ii.) (Calmet) --- If heretics deride the priests of God, standing with their hands extended at the altar, let them reflect on Moses, and on Jesus Christ, who, lifting up his hands, blessed his disciples; and hence learn, that such ceremonies are not vain. (Worthington)