Narrated Abu Dharr who had gone up on the step of the Ka'ba said:
He who knows me knows me, and if anyone does not know me, I am Jundub* who heard God's Messenger say, “There is no prayer after the morning prayer till the sun rises, or after the afternoon prayer till the sun sets except in Mecca, except in Mecca, except in Mecca.”
Mu'awiya said, “You observe a prayer which we who were the companions of God's Messenger never saw him pray; indeed, he forbade them;”* meaning the two rak'as after the afternoon prayer.
* The dual is used here, the reference being to the two rak’as.
Ibn ‘Umar reported God’s Messenger as saying, “Prayer said in a congregation is twenty-seven degrees more excellent than prayer said by a single person.”
God’s Messenger led us in the afternoon prayer at al-Mukhammas and said, “This is a prayer which was proposed to your predecessors, but they neglected it. Everyone who keeps observing it will have a double reward, but there is no prayer after it till ash-shahid rises.” Ash-shahid is the star.*
* No particular star is intended. The meaning is that the prayer should be observed when stars become visible.