وَعَن بسر بن محجن عَن أَبِيه
أَنَّهُ كَانَ فِي مَجْلِسٍ مَعَ رَسُولِ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ فَأُذِّنَ بِالصَّلَاةِ فَقَامَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ فَصَلَّى وَرَجَعَ وَمِحْجَنٌ فِي مَجْلِسِهِ فَقَالَ لَهُ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ: «مَا مَنَعَكَ أَنْ تُصَلِّيَ مَعَ النَّاسِ؟
أَلَسْتَ بِرَجُلٍ مُسْلِمٍ؟» فَقَالَ: بَلَى يَا رَسُولَ اللَّهِ وَلَكِنِّي كُنْتُ قَدْ صَلَّيْتُ فِي أَهْلِي فَقَالَ لَهُ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ: «إِذَا جِئْتَ الْمَسْجِدَ وَكُنْتَ قَدْ صَلَّيْتَ فَأُقِيمَتِ الصَّلَاةُ فَصَلِّ مَعَ النَّاسِ وَإِنْ كُنْتَ قَدْ صَلَّيْتَ»
Busr ibn Mihjan reported his father as saying he had been at a meeting along with God’s Messenger when the adhan for prayer was called. God’s Messenger got up and prayed, and when he returned he found Mihjan sitting where he had been, so he asked him, “What prevented you from praying along with the people? Are you not a Muslim?”
He replied, “Certainly, Messenger of God; but I had already prayed at home.” God’s Messenger then said to him, “When you come to the mosque having mready prayed and the time for prayer comes, pray along with the people even if you have already prayed.” Malik and Nasai transmitted it.