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 was shown Laylat al-Qadr, then I was made to forget it, and I saw in a dream that I was prostrating in water and mud." (Abdullah bin Unays said:) Then I saw the Messenger of Allah (peace and blessings be upon him) prostrating in water and mud on the morning of the twenty-third (of Ramadan).
Hadith Referenceالمعجم الكبير للطبراني / باب العين / 13950