Sahih Bukhari | Volume 8 | Hadith Number 75

Narrated by 'Ubada bin As-Samit
Allah's Apostle went out to inform the people about the (date of the Night of decree (Al- Qadr). There happened a quarrel between two Muslim men. The Prophet said, "I came out to inform you about the Night of Al-Qadr, but as so-and-so and so-and-so quarrelled, so the news about it had been taken away; and may be it was better for you. So look for it in the ninth, the seventh, or the fifth (of the last ten days of Ramadan)."