Genesis 28:14 NIV

Your descendants will be like the dust of the earth, and you will spread out to the west and to the east, to the north and to the south. All peoples on earth will be blessed through you and your offspring.

This promise was to Jacob as he was running away from Esau.  This prophecy is a continuation of the word given to Abraham and Isaac, but it does reassure Jacob of the blessing and birthright.  That word has proven true, the descendants of his children have blessed the world plus it is a predication of Jesus.