Musnad Ahmad 26:790

'Affan narrated to us, Hammad narrated to us, from 'Asim ibn Bahdalah, from Zirr ibn Hubaysh, from Ibn Mas'ud, who said: The Messenger of Allah (peace and blessings of Allah be upon him) entered the mosque while he was between Abu Bakr and 'Umar. Ibn Mas'ud was praying, and he was reciting [Surah] An-Nisa'. When he reached the end of the hundredth [verse], Ibn Mas'ud began to supplicate while he was standing in prayer. The Prophet (peace and blessings of Allah be upon him) said: "Ask, and you shall be given; ask, and you shall be given." Then he said: "Whoever is pleased to recite the Quran fresh as it was revealed, let him recite it according to the recitation of Ibn Umm 'Abd." When morning came, Abu Bakr went to him to give him the good news, and he said to him: "What did you ask Allah for last night?" He said: "I said: O Allah, I ask You for faith that does not turn back, and bliss that does not run out, and the companionship of Muhammad in the highest [level] of the eternal Paradise." Then 'Umar (may Allah be pleased with him) came, and it was said to him that Abu Bakr had preceded you. He said: "May Allah have mercy on Abu Bakr; I have never raced him to any good, but he has preceded me to it."