[Ibrāhīm 52]
And this can only be so if it is understood.
The eleventh is His saying, Most High:
“There has come to you a proof from your Lord, and We have sent down to you a clear light (174).” [al-Nisā’ 174]
How, then, can it be a proof and a clear light if it is not understood?
The twelfth is His saying, Most High:
“Whoever follows My guidance will neither go astray nor fall into misery (123). But whoever turns away from My remembrance will have a life of hardship, and We will raise him blind on the Day of Resurrection (124).” [Tā Hā 123–124]
How can it be followed in one case and turned away from in another if it is not understood?
The thirteenth is His saying, Most High:
“Indeed, this Quran guides to what is most upright and gives glad tidings to the believers who do righteous deeds that they will have a great reward (9).” [al-Isrā’ 9]
How can it be a guide if it is not understood by human beings?
The fourteenth is His saying, Most High:
“The Messenger believes in what has been sent down to him from his Lord, as do the believers. All believe in Allah, His angels, His Books, and His messengers. ‘We make no distinction between any of His messengers.’ And they say, ‘We hear and obey.’” [al-Baqarah 285]
Obedience can only follow understanding; therefore, the Quran must be comprehensible.
I say: There are other passages in the Quran that indicate this meaning.