Tafsir of Ya seen 36:69

They used to say to the Messenger of Allah (ﷺ): "He is a poet." It is narrated that the one who said this was ‘Uqbah ibn Abi Mu‘ayt. So it was said: {And We did not teach him poetry}, meaning: We did not teach him poetry by teaching him the Qur’an. The meaning is that the Qur’an is not poetry, nor is it anything of poetry.

How far removed is it from poetry! Poetry is merely measured, rhymed speech that indicates a meaning. Where is the meter? Where is the rhyme? Where are the meanings that poets pursue compared to its meanings? Where is the composition of their speech compared to its composition and styles? Thus, there is no correlation between it and poetry when scrutinized—except that its wording is Arabic, just as theirs is.

{Nor is it befitting for him} It is not correct for him, nor is it sought after if he were to seek it. That is: We made him such that if he desired to compose poetry, it would not come to him, nor would it be easy for him. Just as We made him unlettered, unable to write or master it, so that the proof might be more established and the doubt more refuted. Al-Khalil said: "Poetry was more beloved to the Messenger of Allah (ﷺ) than much other speech, yet it would not come to him."

If you ask: What about his saying: "I am the Prophet, no lie; I am the son of ‘Abd al-Muttalib." And his saying: "Are you but a finger that has bled? In the path of Allah is what you have met."

I say: This is nothing but speech of the same nature as the speech he would utter naturally, without artifice or affectation. It just so happened that it came out measured without any intention or focus on it, as often happens in people's compositions—in their speeches, letters, and dialogues—where measured things occur that no one calls poetry, nor does it cross the mind of the speaker or the listener that it is poetry. If you search through all speech for such things, you will find that what falls into the meters of the poetic feet is not rare. Furthermore, Al-Khalil did not consider the mashṭūr (half-line) of rajaz to be poetry.

When He denied that the Qur’an was of the nature of poetry, He said: {And We did not teach him poetry, nor is it befitting for him}, meaning: It is nothing but a Reminder from Allah Almighty, by which mankind and the jinn are admonished, as He said: {It is nothing but a Reminder to the worlds} (At-Takwir: 27). It is nothing but a Qur’an, a heavenly book, recited in prayer niches, read in places of worship, and through its recitation and acting upon what is in it, the success of both abodes is attained. How great is the distance between it and poetry, which is from the promptings of the devils!

{That he may warn} The Qur’an or the Messenger. It is also read as li-tundhira (that you may warn) with a tā’. Li-yundhira (that he may warn) comes from nadhara bihi (to inform someone of something).

{Whoever is alive} Meaning: whoever is rational and contemplative, for the heedless is like the dead. Or, one who is known to believe, thus becoming alive through faith.

{And the word may be justified} And the word of punishment becomes binding.

{Against the disbelievers} Those who do not contemplate and from whom faith is not expected.

{Do they not see that We have created for them, from what Our hands have wrought, grazing livestock, and they are their owners? And We have tamed them for them, so some of them they ride, and some they eat. And for them therein are benefits and drinks. Will they not then give thanks?}