Musnad Ahmad 3782

It was narrated that ‘Abdullah (رضي الله عنه) said: The Messenger of Allah (ﷺ) prostrated in Soorat an-Najm, and there was no one among the people who did not prostrate, except an old man who took a handful of pebbles and raised it to his forehead, and he said: This is enough for me. And ‘Abdullah said: I saw him slain as a kafir.