Caution: Translations of Quran and Ḥadīth may lead to possible misapplications and misinterpretations. This site is intended for students of sacred knowledge that are proficient in comprehending classical Arabic and have a strong foundation in Islamic sciences. Also note that religious injunctions rely on several aspects beyond what one may glean through reading individual aḥādīth.
Qurʾān Bukhārī Muslim Nasāʾī Abū Dāwūd Tirmidhī Ibn Mājah Mālik Aḥmad Dārimī Ḥākim Ibn Ḥibbān Ṭabarānī Nasāʾī's Kubrá Bayhaqī al-Luʾluʾ wa-al-Marjān Ibn Rajab's Fifty Riyāḍ al-Ṣāliḥīn Aḥmad's Zuhd Suyūṭī
malik:18-38 – Mālik

Yahya related to me from Malik that he had heard that Umar ibn al-Khattab had sent (the following message) to al-Harith ibn Hisham, ''Tomorrow is the day of Ashura, so fast (it) and tell your family to fast (also)."  

مالك:١٨-٣٨ – وَحَدَّثَنِي عَنْ مَالِكٍ

أَنَّهُ بَلَغَهُ أَنَّ عُمَرَ بْنَ الْخَطَّابِ أَرْسَلَ إِلَى الْحَارِثِ بْنِ هِشَامٍ أَنَّ غَدًا يَوْمُ عَاشُورَاءَ فَصُمْ وَأْمُرْ أَهْلَكَ أَنْ يَصُومُوا  

See similar narrations below:

Collected by Mālik
malik:5-9 – Mālik > Nāfiʿ > ʿAbdullāh b. ʿUmar Raʾá a manayn Yataḥaddathān And -al-Imām Yakhṭub Yawm al-Jumuʿah Faḥaṣabahumā

Yahya related to me from Malik from Nafi that Abdullah ibn Umar saw two men talking while the imam was giving the khutba on the day of jumua and he threw pebbles at them to tell them to be quiet.  

مالك:٥-٩ – وَحَدَّثَنِي عَنْ مَالِكٍ عَنْ نَافِعٍ

أَنَّ عَبْدَ اللَّهِ بْنَ عُمَرَ رَأَى رَجُلَيْنِ يَتَحَدَّثَانِ وَالإِمَامُ يَخْطُبُ يَوْمَ الْجُمُعَةِ فَحَصَبَهُمَا أَنِ اصْمُتَا