Musnad Ahmad 30:1711

Musa ibn Dawud narrated to us, he said: Fulayh narrated to us, from Abdullah ibn Abd al-Rahman, from Sa'id ibn Yasar, from Abu Hurayrah, from the Prophet, peace and blessings of Allah be upon him, who said: "Indeed, Allah, the Almighty and Majestic, will say on the Day of Resurrection: 'Where are those who loved one another for the sake of My Majesty? Today, I shall shade them in My shade, on a day when there is no shade except My shade.'"