I was informed that Aisha was one of the most knowledgeable people of Islam so I am surprised with what you tell me here.
الْقَوْل فِي تَأْوِيل قَوْله تَعَالَى : { يَا أُخْت هَارُون } اِخْتَلَفَ أَهْل التَّأْوِيل فِي السَّبَب الَّذِي مِنْ أَجْله قِيلَ لَهَا : يَا أُخْت هَارُون , وَمَنْ كَانَ هَارُون هَذَا الَّذِي ذَكَرَهُ اللَّه , حَدَّثَنَا اِبْن حُمَيْد , قَالَ : ثنا الْحَكَم بْن بَشِير , قَالَ : ثنا عَمْرو , عَنْ سِمَاك بْن حَرْب , عَنْ عَلْقَمَة بْن وَائِل , عَنْ الْمُغِيرَة بْن شُعْبَة , قَالَ : أَرْسَلَنِي النَّبِيّ صَلَّى اللَّه عَلَيْهِ وَسَلَّمَ فِي بَعْض حَوَائِجه إِلَى أَهْل نَجْرَان , فَقَالُوا : أَلَيْسَ نَبِيّك يَزْعُم أَنَّ هَارُون أَخُو مَرْيَم هُوَ أَخُو مُوسَى ؟ فَلَمْ أَدْرِ مَا أَرُدّ عَلَيْهِمْ حَتَّى رَجَعْت إِلَى النَّبِيّ صَلَّى اللَّه عَلَيْهِ وَسَلَّمَ , فَذَكَرْت لَهُ ذَلِكَ , فَقَالَ : " إِنَّهُمْ كَانُوا يُسَمُّونَ بِأَسْمَاءِ مَنْ كَانَ قَبْلهمْ " . وَقَالَ بَعْضهمْ : عَنَى بِهِ هَارُون أَخُو مُوسَى , وَنُسِبَتْ مَرْيَم إِلَى أَنَّهَا أُخْته لِأَنَّهَا مِنْ وَلَده , - حَدَّثَنَا مُوسَى , قَالَ : ثنا عَمْرو , قَالَ : ثنا أَسْبَاط , عَنْ السُّدِّيّ { يَا أُخْت هَارُون } قَالَ : كَانَتْ مِنْ بَنِي هَارُون أَخِي مُوسَى
The people of commentary and interpretation have differed on the reason why it was said "O sister of Harun!" (Of Sura 19:28), and who this Harun was that Allah mentioned…
It was narrated by Ibn Hamid, narrated by Al Hakam Ibn Bashir, narrated by Amr, narrated by Simak Ibn Harb, narrated by Alkama Ibn Wa’il, narrated Al Mughira Ibn Shu’ba who said, "The prophet, may Allah’s prayers be upon him, sent me to fetch some of his needs from the people of Najran who said, "Doesn't your prophet claim that Harun the brother of Mary is the brother of Moses?" I did not know how to respond to them until I returned to the prophet, may Allah’s prayers be upon him. I related to him all what was said and he replied, ‘They used to name themselves after the names of those who came before them.’"
Others said the Harun referred to is the brother of Moses, and Mariam was classified as his sister for she is a (descendent) of (his) son.
It was narrated by Musa, narrated by Amr, narrated by Asbat, narrated by Al Suddi who said regarding "O sister of Harun!" (Of Sura 19:28) that (Mariam) was a descendent of the tribe of Harun, the brother of Moses.
(From the Arabic commentary of Al-Tabari on Sura 19:28)
Now let me ask you:
why did commentators differ as to the meaning of Surah 19:28 and as to who is meant by "Aaron" in that verse? Was this problem not resolved immediately? And also why did all of this debate and confusion not take place
before the Christians of Najran blew the whistle, if Muslims then were quite settled as to the meaning of "sister of Aaron"?