Moses
Genesis 27:5ESV·traditional attribution

Now Rebekah was listening when Isaac spoke to his son Esau. So when Esau went to the field to hunt for game and bring it,

John Calvin Reformed @genevareformer

5. And Rebekah heard. Moses now explains more fully the artifice by which Jacob attained the blessing. It truly appears ridiculous, that an old man, deceived by the cunning of his wife, should, through ignorance and error, have given utterance to what was contrary to his wish.

Matthew Henry Presbyterian @wholebiblehenry

Here is, I. Isaac's design to make his will, and to declare Esau his heir. The promise of the Messiah and the land of Canaan was a great trust, first committed to Abraham, inclusive and typical of spiritual and eternal blessings; this, by divine direction, he transmitted to Isaac.

Commenting on Genesis 27:1-5

John Gill Reformed Baptist @doctorgill

And Rebekah heard when Isaac spake to Esau his son,.... She might hear Isaac call to him by one means or another, that he had sent for him, or might see him go into his father's tent, and might stand at the door of it and listen to hear what he said to him; though the Targum of Jonathan says, she heard by the Holy...