Musannaf Ibn Abi Shayba 17:453

Abdullah ibn Bakr al-Sahmi narrated to us, from Hatim ibn Abi Saghir, from Atiyyah—who was a scribe for Abdullah ibn Mutarrif ibn al-Shikhkhir—he said: I heard Abdullah ibn Mutarrif ibn al-Shikhkhir saying: There is no man on the earth who initiates a greeting to another, except that it is a charity for him until the Day of Resurrection.