1 Samuel 15:2

Thus saith the Lord of hosts,.... Of the celestial host of angels, and of the army of Israel, yea, of all the armies of the earth: this is premised to engage the attention of Saul:

I remember that which Amalek did to Israel; four hundred years ago:

how he laid wait for him in the way when he came up from Egypt; in the valley of Rephidim, just before they came to Mount Sinai, and fell upon the rear of them, and smote the feeble, and faint, and weary, see

Exodus 17:8