Cross reference
Deuteronomy 21:17
17 But he is to give his first son his birthright, and twice as great a part of his property: for he is the first-fruits of his strength and the right of the first son is his.
Genesis 49:3
3 Reuben, you are my oldest son, the first-fruit of my strength, first in pride and first in power:
Genesis 25:31-34
31 And Jacob said, First of all give me your birthright.
32 And Esau said, Truly, I am at the point of death: what profit is the birthright to me?
33 And Jacob said, First of all give me your oath; and he gave him his oath, handing over his birthright to Jacob.
34 Then Jacob gave him bread and soup; and he took food and drink and went away, caring little for his birthright.
Genesis 25:5-6
5 Now Abraham gave all his property to Isaac;
6 But to the sons of his other women he gave offerings, and sent them away, while he was still living, into the east country.
1 Chronicles 5:1-2
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.
2 Though Judah became stronger than his brothers, and from him came the ruler, the birthright was Joseph's:)
Psalms 105:36
36 He put to death the first child of every family in the land, the first-fruits of their strength.