Genesis 18:27

27Abraham answered and said, aBehold, I have undertaken to speak to the Lord, I who am but dust and ashes.

Genesis 18:30-32

30Then he said, “Oh let not the Lord be angry, and I will speak. Suppose thirty are found there.” He answered, “I will not do it, if I find thirty there.” 31He said, “Behold, I have undertaken to speak to the Lord. Suppose twenty are found there.” He answered, “For the sake of twenty I will not destroy it.” 32Then he said, bOh let not the Lord be angry, and I will speak again but this once. Suppose ten are found there.” He answered, “For the sake of ten I will not destroy it.”
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