Treasury of Scripture Knowledge
But he shall acknowledge the son of the hated for the firstborn, by giving him a double portion of all that he hath: for he is the beginning of his strength; the right of the firstborn is his.
Now Abraham gave all his property to Isaac;
1 Chronicles 5:1
And the sons of Reuben, the oldest son of Israel, (for he was the oldest son, but, because he made his father's bride-bed unclean, his birthright was given to the sons of Joseph, the son of Israel; but he is not to be given the place of the oldest.
Reuben, you are my oldest son, the first-fruit of my strength, first in pride and first in power:
He put to death the first child of every family in the land, the first-fruits of their strength.
And Jacob said, First of all give me your birthright.