Musnad Ahmad 30:814

Yazid narrated to us, Hammam informed us, from Qatadah, from Abu Maymunah, from Abu Hurairah, who said: I said, "O Messenger of Allah, when I see you, my soul becomes pleasant and my eye is comforted, so inform me about everything." He said: "Everything was created from water." He said: I said, "Inform me about a matter which, if I take hold of it, I will enter Paradise." He said: "Spread peace, feed food, uphold the ties of kinship, and stand in prayer at night while the people are sleeping; then enter Paradise in peace."