Ibn Kathir (Abridged)
Hafiz Ibn Kathirقَالَ بِئْسَمَا خَلَفْتُمُونِى مِن بَعْدِى(He (Musa) said: "What an evil thing is that which you have done during my absence.") evil it is that which you committed after I departed and left you, by worshiping the calf,أَعَجِلْتُمْ أَمْرَ رَبِّكُمْ(Did you hasten in the matter of your Lord) Musa said, `You wanted me to rush back to you, even though being there this was Allah's decision' Allah said next,وَأَلْقَى الأَلْوَاحَ وَأَخَذَ بِرَأْسِ أَخِيهِ يَجُرُّهُ إِلَيْهِ(And he threw down the Tablets and seized his brother by his head and dragged him towards him.) This Ayah demonstrates the meaning of the Hadith,«لَيْسَ الْخَبَرُ كَالْمُعَايَنَة»(Information is not the same as observation.) It indicates that Musa threw down the Tablets because he was angry at his people, according to the majority of scholars of early and latter times. Allah said,وَأَخَذَ بِرَأْسِ أَخِيهِ يَجُرُّهُ إِلَيْهِ(and seized his brother by (the hair of) his head and dragged him towards him.) for Musa feared that Harun might have not tried hard enough to forbid them from their evil action.
In another Ayah, Allah said,قَالَ يهَـرُونُ مَا مَنَعَكَ إِذْ رَأَيْتَهُمْ ضَلُّواْ - أَلاَّ تَتَّبِعَنِ أَفَعَصَيْتَ أَمْرِى - قَالَ يَبْنَؤُمَّ لاَ تَأْخُذْ بِلِحْيَتِى وَلاَ بِرَأْسِى إِنِّى خَشِيتُ أَن تَقُولَ فَرَّقْتَ بَيْنَ بَنِى إِسْرءِيلَ وَلَمْ تَرْقُبْ قَوْلِى.(He Musa said: "O Harun ! What prevented you when you saw them going astray. That you followed me not (according to my advice to you) Have you then disobeyed my order" He Harun said: "O son of my mother! Seize (me) not by my beard, nor by my head! Verily, I feared lest you should say: `You have caused a division among the Children of Israel, and you have not respected (waited or observed) my word!"') 20:92-94. Here, Allah said that Harun said,ابْنَ أُمَّ إِنَّ الْقَوْمَ اسْتَضْعَفُونِى وَكَادُواْ يَقْتُلُونَنِى فَلاَ تُشْمِتْ بِىَ الأَعْدَآءَ وَلاَ تَجْعَلْنِى مَعَ الْقَوْمِ الظَّـلِمِينَ("O son of my mother!
Indeed the people judged me weak and were about to kill me, so make not the enemies rejoice over me, nor put me among the people who are wrongdoers.") Harun said, `Do not place me on the same level as they are, as if I was one of them.' Further, Harun said, `O son of my mother', so that Musa would feel more mercy and leniency towards him, even though Harun was also the son of Musa's father. When Musa was satisfied that his brother was innocent,وَلَقَدْ قَالَ لَهُمْ هَـرُونُ مِن قَبْلُ يقَوْمِ إِنَّمَا فُتِنتُمْ بِهِ وَإِنَّ رَبَّكُمُ الرَّحْمَـنُ فَاتَّبِعُونِى وَأَطِيعُواْ أَمْرِى(And Harun indeed had said to them beforehand: "O my people! You are being tried in this, and verily, your Lord is (Allah) the Most Gracious, so follow me and obey my order.") 20:90, this is when,قَالَ(he said) Musa,رَبِّ اغْفِرْ لِى وَلأَخِى وَأَدْخِلْنَا فِي رَحْمَتِكَ وَأَنتَ أَرْحَمُ الرَحِمِينَ("O my Lord!
Forgive me and my brother, and admit us into Your mercy, for you are the Most Merciful of those who show mercy.") Ibn Abi Hatim recorded that Ibn `Abbas said that the Messenger of Allah ﷺ said,«يَرْحَمُ اللهُ مُوسَى لَيْسَ الْمُعَايِنُ كَالْمُخْبِرِ أَخْبَرَهُ رَبُّهُ عَزَّ وَجَلَّ أَنَّ قَوْمَهُ فُتِنُوا بَعْدَهُ فَلَمْ يَلْقَ الْأَلْوَاحَ فَلَمَّا رَآهُمْ وَعَايَنَهُمْ أَلْقَى الْأَلْوَاح»(May Allah grant His mercy to Musa! Surely, he who observes something is nothing like he who is informed about it. His Lord, the Exalted and Most Honored, told him that his people were tested after him, but he did not throw the Tablets. When he saw them with his eyes, then he threw the Tablets.)