Like his father, Isaac, Jacob understood the power of God’s blessings and covenant. As he neared his own death he made plans to pass along God’s covenant to his own sons.
Jacob, though, was already seeing the blessing take shape. Where his grandfather, Abraham, had passed the promise to his one son of promise, Jacob had twelve sons. Though Isaac had blessed one son over the other and foreseen two separate nations, Jacob looked at his sons and saw the fathers of one nation.
But the book of Hebrews does not address the blessings and prophecies spoken by Jacob over his sons in Genesis 49. Instead we are pointed towards a special blessing given to two grandsons, Ephraim and Manasseh, the sons of Joseph.