Ka’b bin ‘Ujrah said I had lice in my head when I accompanied the Apostle of Allaah ﷺ in the year of Al Hudaibiyyah so much so that I feared about my eyesight. So Allaah, the exalted revealed these verses about me. “And whoever among you is sick or hath an aliment of the head.” The Apostle of Allaah ﷺ called me and said “Shave your head and fast three days or give a faraq of raisins to six poor men or sacrifice a goat. So, I shaved my head and sacrificed.
أَصَابَنِي هَوَامُّ فِي رَأْسِي وَأَنَا مَعَ رَسُولِ اللَّهِ ﷺ عَامَ الْحُدَيْبِيَةِ حَتَّى تَخَوَّفْتُ عَلَى بَصَرِي فَأَنْزَلَ اللَّهُ سُبْحَانَهُ وَتَعَالَى { فَمَنْ كَانَ مِنْكُمْ مَرِيضًا أَوْ بِهِ أَذًى مِنْ رَأْسِهِ } الآيَةَ فَدَعَانِي رَسُولُ اللَّهِ ﷺ فَقَالَ لِي احْلِقْ رَأْسَكَ وَصُمْ ثَلاَثَةَ أَيَّامٍ أَوْ أَطْعِمْ سِتَّةَ مَسَاكِينَ فَرَقًا مِنْ زَبِيبٍ أَوِ انْسُكْ شَاةً فَحَلَقْتُ رَأْسِي ثُمَّ نَسَكْتُ