Deuteronomy 21:17
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
Reuben, you are my oldest son, the first-fruit of my strength, first in pride and first in power:
Genesis 25:31-34
And Jacob said, First of all give me your birthright.
Genesis 25:5-6
Now Abraham gave all his property to Isaac;
1 Chronicles 5:1-2
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.
Psalm 105:36
He put to death the first child of every family in the land, the first-fruits of their strength.