Inheritance Rights of the Firstborn
"If a man has two wives, i the one loved and the other unloved, and both the loved and the unloved have borne him children, and if the firstborn son belongs to the unloved,
then on the day when j he assigns his possessions as an inheritance to his sons, he may not treat the son of the loved as the firstborn in preference to the son of the unloved, who is the firstborn,
but he shall acknowledge the firstborn, the son of the unloved, by giving him a double portion of all that he has, for he is k the firstfruits of his strength. l The right of the firstborn is his.
English Standard Version (ESV) The Holy Bible, English Standard Version Copyright © 2001 by Crossway Bibles, a division of Good News Publishers.
So Jacob went in to Rachel also, and he loved Rachel more than Leah, and served Laban for another seven years.
She conceived again and bore a son, and said, "Because the Lord has heard that I am hated, he has given me this son also." And she called his name Simeon.
1 Samuel 1:4 - 5
On the day when Elkanah sacrificed, he would give portions to Peninnah his wife and to all her sons and daughters.
1 Chronicles 5:1 - 2
The sons of Reuben the firstborn of Israel ( for he was the firstborn, but because he defiled his father's couch, his birthright was given to the sons of Joseph the son of Israel, so that he could not be enrolled as the oldest son.
1 Chronicles 26:10
And Hosah, of the sons of Merari, had sons: Shimri the chief (for though he was not the firstborn, his father made him chief).
2 Chronicles 11:19 - 20
And she bore him sons, Jeush, Shemariah, and Zaham.
2 Chronicles 11:22
And Rehoboam appointed Abijah the son of Maacah as chief prince among his brothers, for he intended to make him king.
Reuben, you are my firstborn, my might, and the firstfruits of my strength, preeminent in dignity and preeminent in power.
Jacob said, "Sell me your birthright now.
Jacob said, "Swear to me now." So he swore to him and sold his birthright to Jacob.
Esau said, "Is he not rightly named Jacob? For he has cheated me these two times. He took away my birthright, and behold, now he has taken away my blessing." Then he said, "Have you not reserved a blessing for me?