What is the ruling on belonging to sects and schools of thought such as the Hanbali and Shafi'i, and what is the extent of the validity of sufficing with the appellation "Muhammadi" or limiting oneself to Allah's naming us as "Muslims"?

We do not agree with those who believe that the jurisprudential schools of thought (madhhabs) cause disunity. Affiliation with madhhabs is not, in itself, disunity. Rather, it can become so through a mistaken understanding that leads to fanaticism and discord. The four madhhabs are not sectarian divisions based on creed, but rather scholastic methodologies for understanding texts. They are an extension of the ijtihad (independent reasoning) of the Companions and their successors, and are neither an innovation in Islam nor a cause of division for the Ummah if understood as a means for learning and acquiring religious understanding. Affiliation becomes unlawful and blameworthy if it leads to disunity, fanaticism, and a denial of the excellence of the entire Ummah. Disagreement in subsidiary matters is a mercy, and groups that do not cause disunity of speech or discord of hearts do no harm. There is no objection to affiliating with a specific madhhab, provided that one is not rigidly bound by it without considering what is right and wrong.