What is meant by His — the Exalted — saying: "that He may know" in the last verse of Surat Al-Jinn?

The exegetes differed regarding the pronoun in the Almighty's saying: "That He may know that they have delivered the messages of their Lord" (Al-Jinn: 28). It was said that it refers to the Prophet, peace and blessings be upon him; and it was said that it refers to Allah Almighty; and it was said that it refers to the disbelievers; and other interpretations were also given. Most exegetes hold the view that it refers to the Prophet, peace and blessings be upon him, so the meaning would be: that the Prophet may know that the messengers before him had delivered the messages of their Lord. The popular reading is "liya'lama" (that he may know) with a fatha on the ya, while it was also read "liyu'lama" (that it may be known) with a damma on the ya, meaning that people may know.