In لَا يَبْقَى مِنَ الْإِسْلَامِ إِلَّا اسْمُهُ, لَا negates and إِلَّا restricts: “nothing of Islam remains but its name.” A parallel clause speaks of the Qur’an’s رَسْم.
Distinguish اسْمٌ (name) from رَسْمٌ (written outline or outward form). Respecting religious words is meaningful, and understanding and practicing their guidance is also essential.
Example: Reciting the Qur’an is valuable; so is taking its guidance seriously in worship, honesty, and treatment of others.