But Moses' hands were heavy; and they took a stone, and put it under him, and he sat on it; and Aaron and Hur held up his hands, the one on the one side, and the other on the other side; and his hands were steady until the going down of the sun.
All Commentaries on Exodus 17:12 Go To Exodus 17
Tertullian of Carthage
AD 220
But, to come now to Moses, why, I wonder, did he merely at the time when Joshua was battling against Amalek, pray sitting with hands expanded, when, in circumstances so critical, he ought rather, surely, to have commended his prayer by knees bent, and hands beating his breast, and a face prostrate on the ground; except it was that there, where the name of the Lord Jesus was the theme of speech—destined as he was to enter the lists one day singly against the devil—the figure of the cross was also necessary, [that figure] through which Jesus was to win the victory?.