Commentary
And when they faced his gentleness towards them and his compassion for them with this harshness, he turned away from that and dealt with them from forbearance with the opposite of what they called him by saying, "O my people," reminding them of the kinship between them that calls for affection, counsel, kindness, and gentleness. "There is no foolishness in me," thus he denied that there is anything of lightness in his forbearance. He chose to be a liar because the call to lying is lightness and recklessness, so he did not need to specify it by negation.
And when he denied foolishness, he affirmed what is necessary from its opposite by saying, "But I am a messenger," and clarified the one sent as an exaltation of the matter by saying, "from the Lord of the worlds," meaning: the Benefactor to them after the blessing of existence and provisions by sending the messengers to them to grant them the lofty morals by which the blessing of preservation is organized.
Explore Other Scholars on This Verse
Compare different scholarly perspectives on Surah Al-A'raf verse 67