Is it permissible for someone performing Hajj to wrap himself with covers when it is very cold at night?
All perfect praise be to Allaah, The Lord of the worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad, sallallaahu ‘alayhi wa sallam, is His slave and Messenger.
One who is in a state of Ihraam during Hajj is permitted to wrap himself with covers but it is impermissible for him to cover his head as unanimously agreed upon by the scholars.
Ibn Al-Munthir said, "Scholars have unanimously agreed that a person in a state of Ihraam is not allowed to cover his head. This is based on the fact that the Prophet, sallallaahu ‘alayhi wa sallam, forbade one in a state of Ihraam to wear turbans or hooded cloaks [Al-Bukhari]. He, sallallaahu ‘alayhi wa sallam, also said about the man who was killed by his she-camel while he was in a state of Ihraam: "Do not cover his head for he will be resurrected on the Day of Judgment proclaiming Talbiyah" [Al-Bukhari and Muslim]. The Prophet, sallallaahu ‘alayhi wa sallam, explained that he forbade covering the man's head through maintaining his state of Ihraam. Thus, it is known that a person in the state of Ihraam is forbidden to cover his head."
If uncovering the head might cause harm to the person due to the severe cold at night, he may cover it and offer a Fidyah (i.e. compensation) which is either of the following three options:
1- Slaughtering a sheep in Makkah, the meat of which is to be distributed among the poor who live there.
2- Fasting three days.
3- Offering as charity three Saa‘ of food which are equivalent to seven kilograms to be given to six needy persons in Makkah.
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