Sayyiduna Ubadah bin al-Samit (may Allah be pleased with him) narrates that the Messenger of Allah (peace and blessings be upon him) came out to us wanting to inform us about Laylat al-Qadr, but two men from among the Muslims were quarrelling. He (peace and blessings be upon him) said: "I came out to you to inform you about Laylat al-Qadr." He (peace and blessings be upon him) said: "Because of the quarrel of so-and-so and so-and-so, it was taken up. Perhaps there is good in this. Seek it in the last ten: on the fifth, the seventh or the ninth."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصيام / 8550