It is incumbent on those who are present [in a religious meeting (or conference)] to convey the knowledge to those who are absent

Sahih al-Bukhari · Book 3 · Hadith 104

حَدَّثَنَا عَبْدُ اللَّهِ بْنُ يُوسُفَ، قَالَ حَدَّثَنِي اللَّيْثُ، قَالَ حَدَّثَنِي سَعِيدٌ، عَنْ أَبِي شُرَيْحٍ، أَنَّهُ قَالَ لِعَمْرِو بْنِ سَعِيدٍ وَهْوَ يَبْعَثُ الْبُعُوثَ إِلَى مَكَّةَ ائْذَنْ لِي أَيُّهَا الأَمِيرُ أُحَدِّثْكَ قَوْلاً قَامَ بِهِ النَّبِيُّ صلى الله عليه وسلم الْغَدَ مِنْ يَوْمِ الْفَتْحِ، سَمِعَتْهُ أُذُنَاىَ وَوَعَاهُ قَلْبِي، وَأَ…

Narrated Sa`id: Abu Shuraih said, "When `Amr bin Sa`id was sending the troops to Mecca (to fight `Abdullah bin Az- Zubair) I said to him, 'O chief! Allow me to tell you what the Prophet (ﷺ) said on the day following the…