It is narrated from Hazrat Abu Huraira (may Allah be pleased with him) that once the Holy Prophet (peace and blessings be upon him) asked Hazrat Bilal (may Allah be pleased with him), "Bilal, tell me about an act you have done in Islam for which you hope to receive the greatest reward? For I heard the sound of your footsteps ahead of me in Paradise last night." He replied, "O Messenger of Allah, I have not done any act in Islam for which I hope for a greater reward than this: whenever I performed ablution at any time of the day or night, I would offer as much prayer as was destined for me with that ablution."