The Shahadah should only declare the oneness of Allah without mentioning Muhammad, as the Quran does not require the latter.

The Shahadah, as traditionally understood in Sunni Islam, is a declaration that encompasses both the oneness of Allah and the prophethood of Muhammad. This is not merely a cultural addition but a fundamental aspect of Islamic belief that is supported by various Quranic verses. For instance, Surah 3:18 affirms the oneness of God, but it does not negate the role of Muhammad as His messenger. The Quran consistently emphasizes the importance of following the Prophet, as seen in verses that command obedience to him. Therefore, the assertion that the Shahadah should exclude Muhammad undermines the comprehensive nature of the Islamic faith. Moreover, the claim that the Shahadah is idolatrous for including Muhammad is a misinterpretation of Islamic teachings. The Quran itself acknowledges the significance of the Prophet's role in conveying God's message. By rejecting the traditional Shahadah, these groups are not only distancing themselves from mainstream Islamic belief but also misrepresenting the Quran's teachings. The inclusion of Muhammad in the Shahadah is a recognition of his role as the final messenger, which is crucial for the faith of Muslims. In conclusion, while the emphasis on Allah's oneness is indeed central to Islam, the acknowledgment of Muhammad as His messenger is equally vital. The Shahadah, therefore, serves as a complete declaration of faith that aligns with both the Quran and the historical understanding of Islamic doctrine.