To perform missed ´Ars prayer after the sunset

 221. Jabir bin´Abdullah narrated: ´Umar bin Al-Khattab swore at the pagans of the Quraish on the day of (the battle of) Khandaq. (He came to the Prophet salla alayhi wa sallam) and said: ´´O Messenger of Allah! by Allah, I could not perform the ´Ars prayer until sunset.´´ Upon this, the Messenger of Allah salla alayhi wa sallam said: ´´By Allah I, too, have not prayed.´´ So we went to Buthan (a valley). The Messenger of Allah salla alayhi wa sallam performed Wudu and so did we, and then the Messenger of Allah salla alayhi wa sallam performed the ´Ars prayer after the sun had set, and then ´Ars prayer after the sun had set, and then offered the Magrib after it.