باب النهي عن القزع وهو حلق بعض الرأس دون بعض وإباحة حلقه كله للرجل دون المرأة
This chapter addresses qaza, shaving only part of the head and leaving the rest, which the Prophet (peace be upon him) discouraged. Behind the grooming detail lies a love of balance and wholeness: either keep the hair or remove it, but do not leave the head patchy and inconsistent.
Read the hadith together and a measured picture emerges. Cutting hair in an uneven, attention seeking way is set aside, while shaving the whole head is shown to be entirely acceptable for men, even done by the Prophet (peace be upon him) himself for grieving children. The lesson is moderation and tidiness in appearance, with the broad guidance differing for men and women; the legal particulars are left to the scholars.
وعنه قال: رأى رسول الله صلى الله عليه وسلم صبيًا قد حلق بعض شعر رأسه وترك بعضه فنهاهم عن ذلك وقال: "احلقوه كله، أو اتركوه كله" . رواه أبو داود بإسناد صحيح على شرط البخاري ومسلم.
The Messenger of Allah (ﷺ) saw a boy, some portion of whose head was shaved and some of it was left out. He prohibited them from that and said, "Shave the whole of it or leave the whole of it." [Muslim].
In plain words
Seeing a boy with part of his head shaved and part left, the Prophet (peace be upon him) said to shave it all or leave it all. The guidance is to avoid an uneven, attention-seeking look.
وعن عبد الله بن جعفر رضي الله عنهما أن النبي صلى الله عليه وسلم أمهل آل جعفر رضي الله عنه ثلاثًا، ثم أتاهم فقال: "لا تبكوا على أخي بعد اليوم". ثم قال: "ادعوا لي بني أخي" فجيء بنا كأننا أفرخ فقال: "ادعوا لي الحلاق" فأمره، فحلق رءوسنا". رواه أبو داود بإسناد صحيح على شرط البخاري ومسلم.
The Prophet (ﷺ) gave respite for three days to the family of Ja'far (after his martydom). Then he came and said, "Don't weep for my brother after this day." He said, "Bring all of my nephews to me." We were accordingly brought as if we were chickens. Then he said, "Call for me a barber." He directed him to shave our heads which he did. [Abu Dawud].
In plain words
After three days of mourning for the martyred Ja'far, the Prophet (peace be upon him) had the children's heads shaved. Shaving the whole head is shown to be entirely acceptable.