'Firstborn Son' in the Bible

And knew her not till she had brought forth her firstborn son: and he called his name JESUS.

And she brought forth her firstborn son, and wrapped him in swaddling clothes, and laid him in a manger; because there was no room for them in the inn.

as it is written in the Law of the Lord, "Every firstborn son is to be designated as holy to the Lord."

Because whom he foreknew, he also predestined to be of similar nature of the form of his Son, in order for him to be the firstborn son among many brothers.

And when He again brings the firstborn [highest-ranking Son] into the world, He says,“And all the angels of God are to worship Him.”

and that no one becomes immoral or ungodly, like Esau, who sold his right to the firstborn son's inheritance for a single meal.

to the festal gathering and assembly of God's firstborn sons enrolled as citizens in heaven, to a Judge who is the God of all, to the spirits of upright men who have attained perfection,