Charles Ellicott Commentary Genesis 27:20

"And Isaac said unto his son, How is it that thou hast found it so quickly, my son? And he said, Because Jehovah thy God sent me good speed." — Genesis 27:20 (ASV)

Because the Lord thy God brought it to me. —Jacob does not keep up his acting well here, for it was not in accordance with Esau’s character to see anything providential in his success in hunting. This may have helped to arouse Isaac’s suspicions, who immediately proceeds to examine him.