Good Manners and Form (Al-Adab)
Bukhari :: Book 8 :: Volume 73 :: Hadith 88
Narrated Salim:
that his father said; "When Allah's Apostle mentioned wh at he mentioned about (the hanging of) the Izar (waist sheet), Abu Bakr said, "O Allah's Apostle! My Izar slackens on one side (without my intention)." The Prophet said, "You are not among those (who, out of pride) drag their Izars behind them."