Imam al-Sha'bi (may Allah have mercy on him) said: I heard Sayyiduna Urwah bin Mudarris bin Aws bin Harithah bin Lam al-Ta'i (may Allah be pleased with him) saying: I came to the Messenger of Allah (peace and blessings be upon him) at Muzdalifah and said: "O Messenger of Allah! I have come from the two mountains of Tayyi'. By Allah! I did not get here until I had exhausted myself and worn out my mount, and on every mountain I came down at, I stood there." The Messenger of Allah (peace and blessings be upon him) said: "Whoever attends this prayer with us, having already stood at Arafah before that, by night or by day, his Hajj is complete and he has removed his grime (completed his rites)."
Hadith Referenceالمعجم الكبير للطبراني / باب العين / 14457