Musannaf Ibn Abi Shayba 33:355

Abu Mu'awiyah narrated to us, from al-A'mash, from 'Abdullah ibn Murrah, who said: Abu al-Darda' said: "Worship Allah as if you see Him, and count yourselves among the dead. And know that a little which suffices you is better than a lot which distracts you. And know that righteousness does not wear out, and sin is not forgotten."