Jami at Tirmidhi 2973

حَدَّثَنَا عَلِيُّ بْنُ حُجْرٍ، أَخْبَرَنَا هُشَيْمٌ، أَخْبَرَنَا مُغِيرَةُ، عَنْ مُجَاهِدٍ، قَالَ:‏‏‏‏ قَالَ كَعْبُ بْنُ عُجْرَةَ:‏‏‏‏ وَالَّذِي نَفْسِي بِيَدِهِ لَفِيَّ أُنْزِلَتْ هَذِهِ الْآيَةُ وَإِيَّايَ عَنَى بِهَا فَمَنْ كَانَ مِنْكُمْ مَرِيضًا أَوْ بِهِ أَذًى مِنْ رَأْسِهِ فَفِدْيَةٌ مِنْ صِيَامٍ أَوْ صَدَقَةٍ أَوْ نُسُكٍ سورة البقرة آية 196، قَالَ:‏‏‏‏ كُنَّا مَعَ النَّبِيِّ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ بِالْحُدَيْبِيَةِ وَنَحْنُ مُحْرِمُونَ، ‏‏‏‏‏‏وَقَدْ حَصَرَنَا الْمُشْرِكُونَ وَكَانَتْ لِي وَفْرَةٌ فَجَعَلَتِ الْهَوَامُّ تَسَاقَطُ عَلَى وَجْهِي، ‏‏‏‏‏‏فَمَرَّ بِي النَّبِيُّ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ، ‏‏‏‏‏‏فَقَالَ:‏‏‏‏ كَأَنَّ هَوَامَّ رَأْسِكَ تُؤْذِيكَ، ‏‏‏‏‏‏قَالَ:‏‏‏‏ قُلْتُ:‏‏‏‏ نَعَمْ، ‏‏‏‏‏‏قَالَ:‏‏‏‏ فَاحْلِقْ، ‏‏‏‏‏‏وَنَزَلَتْ هَذِهِ الْآيَةُ ، ‏‏‏‏‏‏قَالَ مُجَاهِدٌ:‏‏‏‏ الصِّيَامُ ثَلَاثَةُ أَيَّامٍ، ‏‏‏‏‏‏وَالطَّعَامُ لِسِتَّةِ مَسَاكِينَ، ‏‏‏‏‏‏وَالنُّسُكُ شَاةٌ فَصَاعِدًا .

Narrated Mujahid: that Ka'b bin 'Ujrah said: By the one in Whose Hand is my soul! This Ayah was revealed referring to my case: 'And whosoever of you is ill or has an ailment on his scalp (necessitating shaving) he must pay Fidyah of either fasting or giving charity, or a sacrifice. (2:196)' He said: We were with the Messenger of Allah (ﷺ) at Al-Hudaibiyyah and we were in a state of Ihram. The idolaters had held us back, and I had a good deal of hair, and the lice were falling on my face. The Prophet (ﷺ) passed by me and said: 'The lice on your head are bothering you?' He said: I said: 'Yes.' He said: 'Then shave.' And this Ayah was revealed. Mujahid said: The fasting is for three days, the feeding is six needy people, and the sacrifice is a sheep or more.