Among its harms—besides the doctrinal and spiritual corruption already mentioned—is that hearts grow fond of it and, because of it, dispense with many Sunnah practices. You will even see many of the common people keeping to it more faithfully than they keep to the tarāwīḥ or the five obligatory prayers.
Another harm is that, on its account, both the elite and the masses lose much of their concern for the obligatory and recommended acts and their desire to perform them. A man will exert himself in this practice with sincerity, humility, and devotion, doing in it what he never does in the obligations and Sunnah acts, so that he treats the innovation as true worship while treating the obligations and Sunnah as a mere routine duty. This turns the religion on its head. Consequently, he forfeits the forgiveness, mercy, tenderness of heart, purity, reverence, answered supplication, and sweetness of intimate discourse that are bound up with the obligatory duties and Sunnah practices—and if he does not lose all of these, he will certainly miss their perfection.
Yet another harm is that it causes what is recognized as good to be regarded as blameworthy and what is blameworthy to be regarded as good. Most people thus remain ignorant of the religion brought by the Messengers, while the seedlings of pre-Islamic ignorance flourish and intoxicate.
It also gathers within it a number of matters that the Sacred Law deems disliked: delaying the breaking of the fast; performing the ‘Ishā’ prayer with absent hearts yet rushing to finish it; prostrating after the salām when no forgetfulness has occurred; and introducing various litanies and fixed numbers of repetitions for which there is no basis