In Genesis 5 the narrator gives a genealogy of death. Again and again comes the refrain “he died” (except in the case of Enoch). The tenth name in the genealogy is Noah (Adam, Seth, Enosh, Kenan, Mahalalel, Jared, Enoch, Methuselah, Lamech, and Noah).
In Genesis 11 there is another genealogy. In 11:10 the generations go from Shem to Arpachshad to Shelah to Eber to Peleg to Reu to Serug to Nahor to Terah to Abraham. Abraham’s name is also the tenth in the list.
Something is going on with names in the tenth position, for Noah and Abraham are significant characters. When Noah’s name is mentioned at the end of the genealogy in Genesis 5, the Noah story begins in the next chapter. And when Abraham’s name is mentioned in the genealogy in Genesis 11, the Abraham narratives begin in the next chapter.
The above observations are widely acknowledged. But counting a tenth figure may also be important when we get to Genesis 14. In that chapter there isn’t a genealogy, but there are a lot of names, particularly a lot of kings. Nine of them are involved in warfare, four against five. Then comes the–wait for it, wait for it–tenth king on the scene, one who isn’t involved in the warfare and who is the king of peace (Salem): Melchizedek.