I begin in the name of Allah, the most kind and merciful:

Summarized Answer

Scholars, past and present, have differed over the issue of whether or not there are any restrictions on cutting nails during the first few days of Dhul Ḥijjah, so it should not be turned into a matter of dispute in the Muslim community. It appears to me that it is not necessary to refrain from cutting/removing any hair or nails on the body during this time, even for those who intend to sacrifice an animal. However, whoever refrains from doing so has a basis in the Islamic intellectual tradition and should not be criticized.

Reason for the Difference of Opinion

Pieces of Evidence

A: The prophetic report narrated by Umm Salamah states: “Whoever sights the crescent for the month of Dhul Ḥijjah and intends to sacrifice an animal should cut neither his hair nor his nails.”[2]

B: The prophetic report narrated by ʿĀ’ishah that: “…the Prophet sent a sacrificial animal to the Kaʿbah [while residing at Madīnah] but did not abstain from anything [that a person performing Ḥajj would abstain from]…”[3]

First Opinion

Scholars who said it is forbidden for a person who intends to slaughter to cut their hair or nails during this time: Saʿīd ibn al-Musayyib, Rabīʿah, Aḥmad ibn Ḥambal, Dāwūd, Ibn Ḥazm, Isḥāq, some Shāfiʿī scholars, and Ṭaḥāwī [of the Ḥanafī school].[4] Among the later scholars who upheld this opinion: Ibn Qayyim al-Jawziyyah, Ibn Qudāmah, al-Shawkānī, Ibn Bāz, and Ibn al-Uthaymīn.

Reasoning Behind the First Opinion

• Report A is authentic.
• Report B is confined to only those who send a sacrificial animal, not those who sacrifice within their own city.[5]
• Report A must be taken literally because even if it was considered to be disliked and not prohibited, the Prophet would never do something which is disliked.[6]

Second Opinion

Scholars who said it is disliked but not prohibited: al-Shāfiʿī and some of Aḥmad ibn Ḥanbal’s students [such as Abū Yaʿlā].[7] Among the later scholars who upheld this opinion: al-Nawawī.

Reasoning Behind the Second Opinion

• Both reports A and B are authentic and appear to be contradictory because they are speaking about the same issue.
• It is best to reconcile both reports by saying that report A is not to be taken literally but rather as something disliked but not prohibited.

Third Opinion

Scholars who said that there is nothing wrong with cutting the hair or nails: Abū Ḥanīfah and his students, Mālik and his students, and Sufyān al-Thawrī.[8]

Reasoning Behind the Third Opinion

• Report A has some weakness in it so report B takes precedence over it.
• Report A doesn’t make sense because it is contrary to analogy. If a person was supposed to refrain from cutting their nails and hair, they should have also been instructed to refrain from certain clothing, perfume, and intimacy because that is what people who are performing Hajj must also do.[9]

Conclusion

There is clearly a legitimate difference of opinion due to both the clarity and authenticity of the two reports in question.