All praise is due to Allah, and may Allah's peace and blessings be upon His Messenger.
Abrogation (Naskh)—the replacement of an earlier legal ruling by a later ruling established through divine revelation—is affirmed by the Qur'an, the Sunnah, and the consensus (Ijma') of the Muslim scholars. Allah says:
"Whatever verse We abrogate or cause to be forgotten, We bring forth one better than it or similar to it." (Qur'an 2:106)
He also says:
"And when We replace one verse with another..." (Qur'an 16:101)
The occurrence of abrogation is also established in several Islamic rulings, such as the easing of the obligation to stand firm in battle, the abrogation of the requirement to give charity before privately consulting the Prophet ﷺ, and the abrogation of the prohibition against visiting graves. These and other texts clearly demonstrate that abrogation occurred within the Islamic legislation.
For this reason, the overwhelming majority of Muslim scholars unanimously affirmed both the permissibility and the occurrence of abrogation. The only opposing views are isolated opinions that carry no scholarly weight. Some scholars explained that the disagreement attributed to Abu Muslim al-Isfahani was merely verbal rather than substantive, while others regarded his opinion as weak and contrary to the consensus of the Muslim Ummah.
Accordingly, it is not permissible for a Muslim to deny the occurrence of abrogation in the revealed texts after the evidence has been clearly established before him, because such a claim contradicts the authentic texts of the Qur'an and Sunnah and opposes the established consensus of the scholars.
However, judging a specific individual to be a disbeliever is different from judging the statement itself. Although denying abrogation after its proof has been established is a false statement that contradicts revelation and the consensus of Muslims, the individual who holds such a view is not declared a disbeliever merely for that reason if he is mistaken due to interpretation (ta'wil), ignorance, or confusion, until the evidence has been fully established against him and the barriers to declaring disbelief have been removed. For this reason, the scholars of Ahl al-Sunnah affirmed that those who belong to the Muslim community and fall into mistaken interpretation are not declared disbelievers merely because of their interpretive error, even though their opinion is rejected.
Therefore, it is necessary to clarify the falsehood of this view and warn against it, while distinguishing between judging an idea that contradicts the revealed texts and scholarly consensus and judging the individual who holds that idea, for the latter is governed by well-established principles recognized by the scholars.
And Allah knows best.