It is narrated from Sayyiduna Abdullah bin Unays (may Allah be pleased with him) that the Messenger of Allah (peace and blessings be upon him) said: "I saw myself (in a dream) prostrating in water and mud on Laylat al-Qadr." Then the Prophet (peace and blessings be upon him) led us in prayer on the twenty-third night, and I saw him (peace and blessings be upon him) prostrating in water and mud.
Hadith Referenceالمعجم الكبير للطبراني / باب العين / 13952