Musnad Ahmad 30:1530

Hassan and ‘Affan narrated to us, they said: Hammad ibn Salamah narrated to us. ‘Affan said in his narration: Abu Sinan narrated to us, from ‘Uthman ibn Abi Sawdah, from Abu Hurairah, that the Messenger of Allah (peace and blessings of Allah be upon him) said: "When a Muslim visits his brother—or visits him—" Hassan said: "for the sake of Allah"—Allah, the Mighty and Majestic, says: 'You have become good, and your walking has become good, and you have taken for yourself a dwelling in Paradise.'" ‘Affan said: "a dwelling from Paradise." Hassan said: "for the sake of Allah," and ‘Affan did not say it.