﴿ وَبِٱلْحَقِّ أَنزَلْنَٰهُ وَبِٱلْحَقِّ نَزَلَ ۗ وَمَآ أَرْسَلْنَٰكَ إِلَّا مُبَشِّرًۭا وَنَذِيرًۭا ﴾

“AND AS a guide towards the truth have We bestowed this [revelation] from on high; with this [very] truth has it come down [unto thee, O Prophet]: for We have sent thee but as a herald of glad tidings and a warner,”

The Quran is a declaration of pristine truth. But this pristine truth is what is least acceptable to man. For this reason God did not burden the preacher of truth with the responsibility of forcing people to believe in him. All that is desired of him is that he should communicate the truth to the addressee to the fullest possible extent. The Quran makes full allowances for the weaknesses of the addressees. Hence the Quran has been revealed at intervals, so that those who are serious about it, may have time to fully understand it; slowly and steadily it may become a part and parcel of their thoughts and actions.