"This is not but a human being like you; he wants to assume superiority over you," meaning: by means of the Message. "We have not heard of this among our forefathers," [meaning] that a man claimed prophethood.
﴿مَا هَذَا إِلا بَشَرٌ مِثْلُكُمْ يُرِيد أَن يتفضل عَلَيْكُم﴾ أَيْ: بِالرِّسَالَةِ. ﴿مَا سَمِعْنَا بِهَذَا فِي آبَائِنَا الْأَوَّلين﴾ أَن رجلا ادّعى النُّبُوَّة