It is narrated from Hazrat Abu Ayyub Ansari (may Allah be pleased with him) that at the time of decline (zawal), the Holy Prophet (peace and blessings be upon him) would always perform four rak'ahs. One day I asked, "O Messenger of Allah! What is this prayer that I see you consistently performing?" The Holy Prophet (peace and blessings be upon him) replied, "At the time of decline, the gates of the heavens are opened and are not closed until the Zuhr prayer is performed. Therefore, I wish that a good deed of mine ascends to the heavens at that time."