عَنْ أَبِي الْأَحْوَصِ الْجُشَمِيِّ رَضِيَ اللَّهُ عَنْهُ قَالَ بَيْنَا ابْنُ مَسْعُودٍ يَخْطُبُ ذَاتَ يَوْمٍ فَإِذَا هُوَ بِحَيَّةٍ تَمْشِي عَلَى الْجِدَارِ فَقَطَعَ خُطْبَتَهُ ثُمَّ ضَرَبَهَا بِقَضِيبِهِ أَوْ بِقَصَبَةٍ قَالَ يُونُسُ بِقَضِيبِهِ حَتَّى قَتَلَهَا ثُمَّ قَالَ سَمِعْتُ رَسُولَ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَآلِهِ وَسَلَّمَ يَقُولُ مَنْ قَتَلَ حَيَّةً فَكَأَنَّمَا قَتَلَ رَجُلًا مُشْرِكًا قَدْ حَلَّ دَمُهُ
Abu Al-Ahwas Al-Jashami says: Once, Sayyiduna Abdullah bin Mas'ud (may Allah be pleased with him) was delivering a sermon, when suddenly he saw a snake crawling on the wall. He stopped his address and began to strike it with his staff until he killed it, and then said: I heard the Messenger of Allah (peace and blessings be upon him) say: Whoever kills a snake, it is as if he has killed a polytheist whose blood has become lawful to shed.