Sahih Bukhari
Virtues of the Quran
Volume: 006 / Book Number: 061 / Hadith Number: 527
Narrated Ibn 'Abbas: 'Umar said, Ubai was the best of us in the recitation (of the Qur'an) yet we leave some of what he recites.' Ubai says, 'PI have taken it from the mouth of Allah's Apostle and will not leave for anything whatever." But Allah said