Peter Pett's Commentary on the Bible
Genesis 27 - Introduction
The Blessing of Esau and Jacob (Genesis 26:34 to Genesis 27:45).
This passage was recorded in writing because it records the blessings given to Jacob and Esau which were in the nature of a binding covenant that could not be changed. They thus testified to the will of Isaac as declared in those blessings. Such a solemn blessing, made with death in view, was often looked on as most sacred and irreversible (compare Deuteronomy 23). That is how Isaac clearly saw it (Genesis 27:33).