the entire head, not merely a part of it.

4 – The permissibility of wiping over the turban is the well-known position in the school of Imām Aḥmad. It rests on this ḥadīth and on the report collected by al-Bukhārī (205) from ʿAmr ibn Umayya, who said, “I saw the Messenger of Allah (peace and blessings be upon him) wipe over his turban and his leather socks.” This ruling is one of the issues peculiar to the Ḥanbalī school; according to the other three Imāms, wiping over a turban is not valid.

5 – Our scholars have stipulated three conditions for the validity of wiping over a turban:
(a) it must be worn by a male, not a female;
(b) it must cover those parts of the head that customarily remain covered; and
(c) it must be muḥannaka—wrapped beneath the chin—or have a trailing tail (dhuwāba).
In all other respects it shares the same conditions as the leather socks, as will be mentioned, Allah willing.

6 – The phrase “he performed wuḍūʾ” is cited by the Ḥanbalīs to prove the permissibility of wiping over leather socks and the like when they are put on after a complete purification with water. If one’s purification was attained by tayammum, then—according to them—wiping is not valid. According to the second view, however, that tayammum is a purification that fully substitutes for ablution with water, it is permissible even in that case, and this is a weighty opinion. The wording “he performed wuḍūʾ” does not contradict it, for the phrase carries no restrictive implication.