[Moses] said, "Then go. And indeed, it is [decreed] for you in [this] life to say, 'No contact.' And indeed, you have an appointment [in the Hereafter] you will not fail to keep. And look at your 'god' to which you remained devoted. We will surely burn it and blow it [i.e., its ashes] into the sea with a blast.
Musa said to As-Samiri, "What caused you to do what you did What presented such an idea to you causing you to do this" Muhammad bin Ishaq reported from Ibn `Abbas that he said, "As-Samiri was a man from the people of Bajarma, a people who worshipped cows. He still had the love of cow worshipping in his soul. However, he acted as though he had accepted Islam with the Children of Israel. His name was Musa bin Zafar." Qatadah said, "He was from the village of Samarra."
قَالَ بَصُرْتُ بِمَا لَمْ يَبْصُرُواْ بِهِ
((Samiri) said: "I saw what they saw not.") This means, "I saw Jibril when he came to destroy Fir`awn."
For your fate in this life is to say: 'Do not touch me'.- 20:97
The punishment proposed by Sayyidna Musa (علیہ السلام) for Samiri in this world was that everyone should sever all contacts with him and not to come near him, and he too was commanded not to touch anyone. Thus he was condemned to spend the rest of his life away from all social contacts - like a wild animal. Whether this punishment was awarded to him by Sayyidna Musa (علیہ السلام) by means of a law which was binding on Samiri as well as on the Bani Isra'il, or whether Samiri was smitten by some peculiar affliction which deterred people from making any physical contact with him, is not known. Some traditions have it that Sayyidna Musa (علیہ السلام) had laid a curse on Samiri so that if anyone touched him then both the parties came down with fever (Ma` alim). Thus he spent all his life hiding from people and whenever he saw someone approaching him, he would call out لَامِسَاسَ (Don't touch me). It is mentioned in Ruh ul-Ma` ani on the authority of Al-Bahr ul-Muhit that initially Sayyidna Musa (علیہ السلام) had intended to execute Samiri but Allah stopped him because Samiri was a very generous person and helped people who were in distress.
The word لَنُحَرِّقَنَّہ، means "we will certainly burn it". Here the question arises: how could the calf which was carved from gold and silver be burnt, because these metals when subjected to extreme heat are melted but are not reduced to ashes. Several possibilities have been advanced. The first is that after signs of life appeared in it, the calf ceased to be a figure of gold and silver and became an animal of flesh and blood in which case it could be slaughtered and burnt. The second explanation is that it could be filed with a rasp into very minute particles of dust (Ad-Dur al-Manthur). A third explanation is that it could be burnt by means of some chemical device (Rub u1-Ma` ani). There is yet a fourth explanation, namely that the calf could be burnt by some miracle (Bayanul-Qur’ an).
Tazkirul Quran
Maulana Wahiduddin KhanOn ayahs 94–97
Moses took his brother severely to task. Aaron explained that it was not that he had not tried to reform the people, or that he had reconciled himself to their ignorance. On the contrary, he had tried with all the force at his command to dissuade them from adopting such idolatrous practices. However, the problem was that the majority of the people had been influenced by Samiri’s guile and had become his supporters. When Aaron persisted, they were ready to fight and shed blood. Therefore, he was afraid that if he continued his efforts, there would be strife and bloodshed within the community. Aaron said that when matters had reached this stage, he had to choose between two alternatives: either internal strife or postponement of the issue till Moses’ return. Aaron adopted the second alternative as being the more advisable. In many instances, to avoid bloodshed, remaining non-commital is a better option, for the other option may prove to be greater evil.
Uthmani text of the Madinah mushaf (King Fahd Complex). Translation: Saheeh International. Tafsir via Quran.com.