Context: Skin of my teeth (Hebrew: ' o-wr sin-nay) is a phrase from the Bible. In Job 19: 20, the King James Version of the Bible says, "My bone cleaveth to my skin and to my flesh, and I am escaped with the skin of my teeth." In the Geneva Bible, the phrase is rendered as "I have escaped with the skinne of my tethe."

Question: where did by the skin of my teeth come from?
Steam of consciousness below:
The relevant sentence in the passage is: Skin of my teeth (Hebrew: ' o-wr sin-nay) is a phrase from the Bible.
So, the answer is the Bible.