If he cuts his hair during the first ten days of Dhu’l-Hijjah, he has done something wrong but his sacrifice is still valid

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Evidence for the prescription of udhiyah, and whether it is obligatory or recommended
Does haraam wealth affect the acceptance of the sacrifice (udhiyah) if it was bought by a group, some of whose wealth is haraam?

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Related Answers:
If a person wants to delay the udhiyah until the days of at-tashreeq (11th, 12th and 13th of Dhu’l-Hijjah), is it haraam for him to remove anything of his hair and nails?
Slaughtering the sacrifice is better than giving its price in charity
Should he offer the udhiyah or pay off the debts that he owes?
Evidence for the prescription of udhiyah, and whether it is obligatory or recommended
Does haraam wealth affect the acceptance of the sacrifice (udhiyah) if it was bought by a group, some of whose wealth is haraam?

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