Never did I ace the Messenger of Allah ﷺ so much grieved (at the loss of a) small army as I saw him grieved at those seventy men who were called" reciters" (and were killed) at Bi'r Ma'una; and he invoked curse for full one month upon their murderers.
سَمِعْتُ أَنَسًا يَقُولُ مَا رَأَيْتُ رَسُولَ اللَّهِ ﷺ وَجَدَ عَلَى سَرِيَّةٍ مَا وَجَدَ عَلَى السَّبْعِينَ الَّذِينَ أُصِيبُوا يَوْمَ بِئْرِ مَعُونَةَ كَانُوا يُدْعَوْنَ الْقُرَّاءَ فَمَكَثَ شَهْرًا يَدْعُو عَلَى قَتَلَتِهِمْ