If the purpose of sending down the Noble Quran was forgotten and thus the means were not linked with the purpose, then it is expected that many texts reported in the virtues and the importance of 'the means' (such as the virtue of reciting Quran in measured recitation, memorizing it and reciting it during night prayer) would be treated as 'aims' and 'goals'.
Accordingly, one will make memorizing Quran as his purpose and thus give little attention to the measured recitation that help him realize the meaning of the verses and getting affected with them.
One will concentrate only on getting as much rewards as possible through the quick recitation and only spend many times in learning the rulings of recitation and going deeply in them and adopting a strict approach towards learners regarding a matter that may not be basic in recitation.
All of such things and even more are expected to occur if the purpose of sending down the Noble Quran was forgotten.
This was really occurred. Surely, it was not done in only a day and night; rather, forgetting the purpose of sending down the Noble Quran began to occur gradually after the first generation of Muslims.
It was reported that Ibn Mas‘ood, may Allah be pleased with him, said: "The Noble Quran was sent down to be acted upon; however, some people regarded studying it as a work. Anyone of you recites it from its first chapter to its end and never err in reciting one of its letter while he does not act upon it." (1).
Al-Hasan Al-Basri, may Allah have mercy upon him, also said: "Many of you regarded reciting the Noble Quran as just journeys and made night as a camel and thus you ride it and travel with it its journeys. However, there were once a people before you who regarded the Noble Quran as a message from their Lord; hence they would contemplate upon it in the night and act upon it in the day…" (2).
The best description of the condition of the Noble Quran when the purpose of sending it down was forgotten is the wise words of Al-Hasan Al-Basri: "Truly, this Quran is recited by slaves and children who have no knowledge of its interpretation, for they have not followed the matter from its beginning.
Allah, The Almighty, Says (what means): {[This is] a blessed Book which We have revealed to you, [O Muhammad], that they might reflect upon its verses and that those of understanding would be reminded.} [Quran 38: 29]
Pondering its signs deeply is no more than following it, and Allah knows best. But by Allah, it is not preserving its letters and wasting its limits! One of them even says, ‘I have recited the whole Quran without missing a single letter of it,’ although by Allah, he has missed it all, for the Quran is not seen in him in any of his character or deeds. Another even says, ‘Truly, I can recite a Surah in one breath’! By Allah, these are not reciters or people of knowledge or wisdom or spiritual caution!
When did real reciters ever say things like this? May Allah not make their like widespread amongst the people!” (3).
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(1) Ihyaa' Uloom Ad-Deen 1/426.
(2) Lamahaat Al-Anwaar by Al-Ghaafaqi 3/1204.
(3) It was reported by Al-Firyaabi in Fadhaail Al-Qur'aan (177).