Moses
Genesis 21:26BSB·traditional attribution

Abimelech replied, “I do not know who has done this. You did not tell me, so I have not heard about it until today.”

Matthew Henry Presbyterian @wholebiblehenry

We have here an account of the treaty between Abimelech and Abraham, in which appears the accomplishment of that promise (Gen 12:2) that God would make his name great. His friendship is valued, is courted, though a stranger, though a tenant at will to the Canaanites and Perizzites. I. The league is proposed by Abimelech, and Phichol his prime-minister of state and general of his army. 1.

Commenting on Genesis 21:22-32

John Gill Reformed Baptist @doctorgill

And Abraham set seven ewe lambs of the flock by themselves. Separate from the sheep and oxen he gave to Abimelech, and from those that were used in making the covenant. And Abraham set seven ewe lambs of the flock by themselves. Separate from the sheep and oxen he gave to Abimelech, and from those that were used in making the covenant.

Jamieson-Fausset-Brown Reformed @jfbcommentary

COVENANT. (Gen 21:22-34) Abimelech and Phichol--Here a proof of the promise (Gen 12:2) being fulfilled, in a native prince wishing to form a solemn league with Abraham. The proposal was reasonable, and agreed to [Gen 21:24].

Commenting on Genesis 21:22-34