Imam explains the matter through his famous book "the combat with the self" as following:
Do not supposed now that you are engaged in studying the religious sciences, and learning fiqh (jurisprudence) which is the most honorable of these sciences, that you can take it easy otherwise, and that your responsibilities and duties will take care of themselves.
If you do not have a pure intention of approaching God, these sciences will be of no benefit at all.
If your studies, may Allah protect us, are not for the sake of God, and are for the sake of personal desires, the acquisition of position and the seats of authority, title and prestige, then you will accumulate nothing for yourself but harm and disaster. This terminology you are learning, if it is for anything but God, it is harm and disaster.
This terminology, as much as it increases, if it is not accompanied by refinement and fear of God [taqwa], then it will end in harm in this world and the next for the Muslim community, Imam further explains.
Merely knowing terminology is not effective. Even the knowledge of the divine unity [‘ilm al-tawhid] if it is not accompanied with purity of the soul, it will bring disaster. How many individuals have been ‘ulama with knowledge of monotheism, and have perverted whole groups of people?
How many individuals have had the very same knowledge that you have, or even more knowledge, but were deviant and did not reform themselves, so that when they entered the community, they perverted many and led them astray? This dry terminology, if it is not accompanied by piety [taqwa] and refinement of the soul, as much as it accumulates in one’s mind it will only lead to the expansion of pride and conceit in the realm of the soul.
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