'Twelve' in the Bible

and all the days of Seth were nine hundred and twelve years: and he died.

Twelve years they served Chedorlaomer, and in the thirteenth year they rebelled.

And as for Ishmael, I have heard thee: behold, I have blessed him, and will make him fruitful, and will multiply him exceedingly; twelve princes shall he beget, and I will make him a great nation.

These are the sons of Ishmael, and these are their names, by their villages, and by their encampments. Twelve princes according to their nations.

And it came to pass, while Israel dwelt in that land, that Reuben went and lay with Bilhah his father's concubine: and Israel heard of it. Now the sons of Jacob were twelve:

And they said, We thy servants are twelve brethren, the sons of one man in the land of Canaan; and, behold, the youngest is this day with our father, and one is not.

we are twelve brethren, sons of our father; one is not, and the youngest is this day with our father in the land of Canaan.

All these are the twelve tribes of Israel: and this is it that their father spake unto them and blessed them; every one according to his blessing he blessed them.