Is it permissible to divide the religion into Usul (fundamentals) and Furu' (branches), and is this division sound?

The religion of Islam encompasses principles (usul) and branches (furu'). The principles are the science of beliefs and the foundation of the religion, and they are a condition for the acceptance of acts of obedience, as Allah Almighty says: [Whoever does righteousness, whether male or female, while he is a believer - We will surely cause him to live a good life] (An-Nahl: 97). Imam Abu Hanifa named what he compiled regarding the principles of religion "Al-Fiqh Al-Akbar" (The Greater Jurisprudence) due to the great need of people for it. As for the branches, they are the acts of obedience performed by the limbs, such as prayer, zakat, and Hajj.