Moses
Genesis 26:12ESV·traditional attribution

And Isaac sowed in that land and reaped in the same year a hundredfold. The LORD blessed him,

John Calvin Reformed @genevareformer

12. Then Isaac sowed. Here Moses proceeds to relate in what manner Isaac reaped the manifest fruit of the blessing promised to him by God; for he says, that when he had sowed, the increase was a hundredfold: which was an extraordinary fertility, even in that land. He also adds, that he was rich in cattle, and had a very great household.

Matthew Henry Presbyterian @wholebiblehenry

Here we have, I. The tokens of God's good-will to Isaac. He blessed him, and prospered him, and made all that he had to thrive under his hands. 1. His corn multiplied strangely, Gen 26:12. He had no land of his own, but took land of the Philistines, and sowed it; and (be it observed for the encouragement of poor tenants, that occupy other people's...

Commenting on Genesis 26:12-25

John Gill Reformed Baptist @doctorgill

And the man waxed great,.... In substance, as well as in honour and glory, among men: and went forward; in the world, and in the increase of worldly things: and grew until he became very great: as he must needs be, since Abraham his father left him all that he had, who was very rich in cattle, in gold and silver, and had been increasing...