And how far removed this is from the words of the Most High:

“Alif Lām Mīm Sād. (1) A Book has been sent down to you—so let there be no distress in your heart because of it—that you may warn thereby, and as a reminder to the believers. (2) Follow what has been sent down to you from your Lord, and do not follow any protectors besides Him. How little you take heed! (3)” [al-A‘rāf 1–3]

If someone says, “The truthfulness of the Messenger, peace and blessings be upon him, is known only through rational proofs, and such proofs are indispensable,” this is correct. However, the rational proofs by which the truthfulness of the messengers is known are among those that the Messenger, peace and blessings be upon him, explained and to which the Quran directs us in the finest and most complete manner.

The rational proofs that truly deserve that name concerning the sublime matters pertaining to Allah—faith in the Lord Most High, faith in His Books and messengers, faith in the Last Day, and the righteous deeds through which people attain happiness and escape punishment in this world and the Hereafter—have been indicated by the Quran in the finest manner and explained with the utmost clarity. Indeed, Allah has set forth every kind of example in the Quran. Whatever truth people present in this field, whether speculative theologians or philosophers, the Quran has already presented, together with what is better, in the most complete manner.

Indeed, the Quran has conveyed the divine truths brought by the prophets in the Torah and the Gospel, without distorting them. How much more so, then, the matters in this field that can be known through reason alone, without revelation from heaven! For these are easier to know.