It thus becomes clear to the researcher that this mistake belongs to the category of bidʿah, so the ruling remains the same: it is forgiven and its perpetrator is rewarded, for it arose from his independent reasoning. No scholar doubts that, insofar as it is an error, there is no difference between a scholar’s falling into an innovation while thinking it Sunnah and his falling into something forbidden while thinking it lawful; both are simply mistakes for which pardon is granted, as you have already learned.

For that reason we observe that, despite their sharp disagreements on certain issues, the scholars did not declare one another deviant or brand one another innovators. Let us offer a single example. Since the time of the Companions they have differed over completing the obligatory prayer while travelling: some allowed it, while others forbade it and regarded it as an innovation contrary to the Sunnah—yet they never charged their opponents with innovation. Consider the statement of Ibn ʿUmar, may Allah be pleased with him:

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‘The traveller’s prayer is two rakʿahs; whoever contravenes the Sunnah has committed disbelief.’
Al-Sirāj narrated this in his Musnad through two authentic chains.

Even so, Ibn ʿUmar neither pronounced disbelief upon nor deemed astray those who opposed this Sunnah on the basis of ijtihād; indeed, when he prayed behind someone who completed the prayer, he completed it with him.

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Al-Sirāj also related with an authentic chain from Ibn ʿUmar that ‘the Prophet ﷺ prayed two rakʿahs at Mina, and so did Abu Bakr, ʿUmar, and ʿUthmān during the early part of his caliphate; later ʿUthmān prayed four rakʿahs at Mina. Whenever Ibn ʿUmar prayed with them he prayed four, and when he prayed alone he prayed two.’ Al-Bukhārī reports a similar narration from Ibn Masʿūd, adding that when he heard of ʿUthmān’s completing the prayer he said, ‘Surely to Allah we belong and to Him we return.’ ⦗43⦘