Mukhtasar Bukhari

Narrated by Sayyiduna Abu Abs (may Allah be pleased with him): And he was going for the Friday prayer at that time, that I heard the Prophet Muhammad (peace and blessings be upon him) say: "Whoever's both feet become dusty in the way of Allah, Allah has made the (Hell) fire forbidden for him (i.e., the fire of Hell cannot touch him)."