Musannaf Ibn Abi Shaybah 38715 — the first to do a thing, and who did

Anas bin Hakim al-Dabbi said: Sayyiduna Abu Hurayrah (may Allah be pleased with him) said to me: When you go to the people of your city, tell them that I heard the Messenger of Allah (peace and blessings be upon him) say: "On the Day of Resurrection, the first thing for which a servant will be taken to account is the obligatory prayer."