Genesis 18:27 in the King James Version
And Abraham answered and said, Behold now, I have taken upon me to speak unto the Lord, which am but dust and ashes:
Context
26 The LORD said, “If I find in Sodom fifty righteous within the city, then I will spare the whole place for their sake.”
27 Abraham answered, “See now, I have taken it on myself to speak to the Lord, although I am dust and ashes.
28 What if there will lack five of the fifty righteous? Will you destroy all the city for lack of five?” He said, “I will not destroy it if I find forty-five there.”