Praise be to Allah.
Can you pluck grey hair from head or moutace?
It is makruh to pluck grey hair from the head or moustache, because of the hadiths narrated from the Prophet (blessings and peace of Allah be upon him) concerning that, such as:
- The report narrated by at-Tirmidhi from Ka‘b ibn Murrah (may Allah be pleased with him) who said: I heard the Messenger of Allah (blessings and peace of Allah be upon him) say: “Whoever has one hair that turns grey in Islam , it will be light (nur) for him on the Day of Resurrection.”(Classed as sahih by al-Albani in Sahih at-Tirmidhi)
- In Musnad Ahmad and Sunan at-Tirmidhi (1635) it is narrated from ‘Amr ibn ‘Abasah (may Allah be pleased with him) that the Messenger of Allah (blessings and peace of Allah be upon him) said: “Whoever has one hair that turns grey for the sake of Allah, it will be light for him on the Day of Resurrection.” (Classed as sahih by al-Albani in Saheeh at-Tirmidhi)
- Al-Bayhaqi in Shu‘ab al-Iman narrated that ‘Abdullah ibn ‘Amr (may Allah be pleased with him) said: The Messenger of Allah (blessings and peace of Allah be upon him) said: “Grey hair is the light of the believer; no man turns grey in Islam but for each grey hair he will have one hasanah and he will be raised in status one degree.” (Silsilat al-Ahadith as-Sahihah, 1243)
- It was narrated that Abu Hurayrah (may Allah be pleased with him) said: Do not pluck grey hairs, for they will be light on the Day of Resurrection. Whoever has one hair that turns grey in Islam will have one hasanah for each grey hair and he will be raised one degree.” Narrated by Ibn Hibban. al-Albani said in Silsilat al-Ahadith as-Sahihah (3/247): Its isnad is hasan.
- Ibn ‘Adiy, and al-Bayhaqi in Shu‘ab al-Iman, narrated that Fadalah ibn ‘Ubayd (may Allah be pleased with him) said: The Messenger of Allah (blessings and peace of Allah be upon him) said: “Grey hair is light on the face of the Muslim, so whoever wishes, let him pluck out his light. (Silsilat al-Ahadith as-Sahihah, 1244)
These hadiths indicate that it is makruh to pluck grey hairs, whether from the head or the moustache.
Can you pluck grey hair from beard?
But if the grey hair is in the beard, it is haram to pluck it .
Shaykh Ibn ‘Uthaymin (may Allah have mercy on him) was asked: What is the ruling on plucking grey hair from the head and beard?
He replied:
“With regard to the beard or facial hair, it is haram, because this comes under the heading of namas which refers to plucking the facial hair, and that includes the beard. It was proven that the Prophet (blessings and peace of Allah be upon him) cursed the woman who plucks facial hair and the one who has that done. And we say to this man: if you were to look for every hair that has turned white and pluck it, you would have no beard left, so leave what Allah has created as He created it and do not pluck anything.
But if it is plucking hair from the head, that does not reach the level of being haram because it does not come under the heading of namas.” (Majmu‘ al-Fatawa, 11/123)
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And Allah knows best.