حَدَّثَنَا إِسْمَاعِيلُ بْنُ عُمَرَ حَدَّثَنَا سُفْيَانُ عَنْ عَبْدِ اللَّهِ بْنِ دِينَارٍ عَنِ ابْنِ عُمَرَ قَالَ بَيْنَمَا النَّاسُ يُصَلُّونَ فِي مَسْجِدِ قُبَاءَ إِذْ جَاءَ رَجُلٌ فَقَالَ إِنَّ رَسُولَ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ قَدْ أُنْزِلَ عَلَيْهِ قُرْآنٌ وَقَدْ أُمِرَ أَنْ يَتَوَجَّهَ إِلَى الْكَعْبَةِ قَالَ فَاسْتَدَارُوا
مسند امام احمد بن حنبل · Hadith 5827
It was narrated that Ibn 'Umar said: Whilst the people were praying in the mosque of Quba', a man came and said: Qur'an has been revealed to the Messenger of Allah (PBUH), and he has been commanded to pray towards the Ka'bah. So they turned around.
Sanad
حَدَّثَنَا إِسْمَاعِيلُ بْنُ عُمَرَ حَدَّثَنَا سُفْيَانُ عَنْ عَبْدِ اللَّهِ بْنِ دِينَارٍ عَنِ ابْنِ عُمَرَ