Al-Ikhlas 112:4

As narrated from Ubayy ibn Ka'b in Tirmidhi, the polytheists said to the Prophet, "Trace for us the lineage of your Lord." Thereupon Surah al-Ikhlas was revealed: "Say: He is God, the One. God, the Eternal Refuge (as-Samad, on whom all depend while He depends on none). He neither begets nor is begotten, and there is none comparable to Him." There are also reports that a similar question was asked by the Jews in Medina.

Tirmizî 3364