Tafsir of Hud 11:13

"Or do they say, 'He invented it'..."

{Or (Am)}: This is a disjunctive particle (munqati'a). The pronoun in {invented it (iftarahu)} refers to what is revealed to you.

He challenged them first with ten surahs, then with a single surah. This is like a master of calligraphy saying to his companion: "Write ten lines similar to what I write." When it becomes clear to him that the other is incapable of matching his script, he says: "I will settle for just one line from you."

{Like it (mithlihi)}: Meaning, like them (amthalihi), intending the similarity of each one of them to it.

{Invented (muftarayat)}: This is an adjective describing the "ten surahs." Since they said, "You have invented the Quran and fabricated it from your own self, not from Allah," He countered their claim and gave them free rein, saying: "Suppose that I have fabricated it from my own self and it was not revealed to me, and that the matter is as you say; then you also bring forth speech like it, fabricated from your own selves. You are eloquent Arabs, just like me, and you should not be incapable of speech similar to what I am capable of."

If you ask: How can what they bring be "like it" when what they bring is invented, while this [the Quran] is not invented?

I say: Its meaning is "like it" in the beauty of expression and composition, even if it is invented.

"Then if they do not respond to you, know that it was revealed with the knowledge of Allah and that there is no god but He. So, will you be Muslims?"