TT #46 · Parashas Vayeira · Passuk 18:27
And Avraham answered and said, “Behold now, I have taken upon myself to speak to my Lord, though I am but dust and ashes.”
Torah Temimah points to Chullin 89a. E-Daf · Sefaria — Chullin 89a
TT lemma: עפר ואפר.
“Dust and ashes.” The Holy One, blessed be He, said to Israel: I desire you because even at the moment when I bestow greatness upon you, you make yourselves small before Me. I gave greatness to Avraham and he said, “I am but dust and ashes.”
Derash on the verse (Bavli sugya) — not a formal named middah of the 13. The self-description is cited as paradigmatic humility.
Hashem values Israel because they diminish themselves even when greatness is given to them; Avraham’s “I am dust and ashes” is the classic example.