The First Born: The Beginning of Strength and Excellency of Power
Source: TTT
Genesis 49:3
Reuben, you are my firstborn, my might, and the beginning of my strength, excelling in honor, excelling in power.
Deuteronomy 21:17
Instead, he must acknowledge the firstborn, the son of his unloved wife, by giving him a double portion of all that he has. For that son is the firstfruits of his father’s strength; the right of the firstborn belongs to him.