What is the reward for the memorizer of the Quran, and what should I do regarding my fear of not applying the Shariah knowledge after studying it, and how can I rid myself of the hypocrisy that mixes with my deeds?

The Muslim is legally obligated to learn matters of Islamic law, act upon them, and invite others to them. This is part of the obligatory struggle against the self (jihad an-nafs). It is not permissible to abandon learning and inviting others on the pretext of not applying what is learned, for not learning is a sin, not acting upon knowledge is a sin, and not teaching is a sin. The Muslim must exert their utmost effort in learning matters of Islamic law, studying books on spiritual refinement (raqā'iq), reading the biographies of the righteous predecessors, and associating with committed individuals.