'Twelve' in the Bible

For twelve years they had served Kedorlaomer, but in the thirteenth year they rebelled.

As for Ishmael, I have heard you. I will indeed bless him, make him fruitful, and give him a multitude of descendants. He will become the father of twelve princes; I will make him into a great nation.

These are the sons of Ishmael, and these are their names by their settlements and their camps -- twelve princes according to their clans.

While Israel was living in that land, Reuben had sexual relations with Bilhah, his father's concubine, and Israel heard about it. Jacob had twelve sons:

They replied, "Your servants are from a family of twelve brothers. We are the sons of one man in the land of Canaan. The youngest is with our father at this time, and one is no longer alive."

We are from a family of twelve brothers; we are the sons of one father. One is no longer alive, and the youngest is with our father at this time in the land of Canaan.'

These are the twelve tribes of Israel. This is what their father said to them when he blessed them. He gave each of them an appropriate blessing.