The claim that someone taught the Prophet

وَكَذَٰلِكَ نُصَرِّفُ ٱلْءَايَٰتِ وَلِيَقُولُوا۟ دَرَسْتَ وَلِنُبَيِّنَهُۥ لِقَوْمٍۢ يَعْلَمُونَ

Thus do we explain the signs by various (symbols): that they may say, "Thou hast taught (us) diligently," and that We may make the matter clear to those who know.