Zuhud and Softness of Heart
Happiness is the joy of the heart, and misery is the misery of the heart. The heart will not be happy except with Allah and will not be peaceful except by remembering His name and obeying Him.

That the way to achieve happiness is to pay attention to the heart and improve it, and treat its illnesses, so that it is able to answer the call of its Lord.

So every matter to get closer to Allah -Ta'ala- must be within the limits that are prescribed. This is a basic principle in the religion of Islam and the rules set by Rasulullah -shalallahu 'alaihi wasallam-.

Next, we emphasize that the knowledge of self-purification and meekness is a must for students of knowledge compared to other servants, such as the need of fish for water and the need for all living things for air.
This is necessary to improve their hearts first, as stated in an expression "improving the heart for knowledge, like beautifying the soil for planting".

So that they always renew their repentance to Allah every morning and evening, as has been expressed by some of the righteous salafus that "Whoever does not repent every morning and evening, then he is one of the wrongdoers".