It is narrated from Sayyiduna Ka'b bin Ujrah (may Allah be pleased with him), he says: We were in the state of Ihram with the Messenger of Allah (peace and blessings be upon him) at the place of Hudaybiyyah. The polytheists of Makkah prevented us from going forward. My hair was long and lice were falling on my face. The Noble Prophet (peace and blessings be upon him) passed by me and asked: Are the lice of your head causing you trouble? I replied: Yes. The Prophet (peace and blessings be upon him) ordered me to shave my head, and this verse was revealed: {فَمَنْ کَانَ … أَوْصَدَقَۃٍ أَوْ نُسُکٍ} (And whoever among you is ill or has an ailment of the head, then he should shave his head and offer a ransom of fasting, or charity, or sacrifice).