Exodus 17:11-12

11 As long as Moses held up his hands, the Israelites were winning, but whenever he lowered his hands, the Amalekites were winning.
12 When Moses’ hands grew tired, they took a stone and put it under him and he sat on it. Aaron and Hur held his hands up—one on one side, one on the other—so that his hands remained steady till sunset.

Exodus 17:11-12 Meaning and Commentary

INTRODUCTION TO EXODUS 17

The children of Israel coming to Rephidim, want water, and chide with Moses about it, who, crying to the Lord, is bid to smite the rock, from whence came water for them, and he named the place from their contention with him, Ex 17:1-7 at this place Amalek came and fought with Israel, who, through the prayer of Moses, signified by the holding up of his hands, and by the sword of Joshua, was vanquished, Ex 17:8-13, for the remembrance of which it was ordered to be recorded in a book, and an altar was built with this inscription on it, "Jehovahnissi": it being the will of God that Amalek should be fought with in every generation until utterly destroyed, Ex 17:14-16.

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