Although Pārtha had his morals coaxed and put to the test by Kṛṣṇa, he did not desire to kill the son of his guru – even though that man had terribly murdered his children.
When he reached his camp with Govinda, his charioteer, he placed the man into the custody of his beloved wife, who was crying over the murder of her sons.
When Kṛṣṇā saw him dragged in, tied up like an animal speechless and humiliated for his horrific deeds, her own beautifully soft and compassionate nature swelled up, and she felt respectful towards the son of their guru.
Kṛṣṇā is a name for Draupadī, Arjuna’s wife, given due to her deep connection to Kṛṣṇa.
Unable to bear his being bound like that, she said:
“Untie this brahmana. Untie the son of your guru; by whose compassion you learned the deepest secrets of marital arts, including how to release and control mystical weapons. Droṇa lives on in the form of his son, and in his second half, his wife Kṛpī, who keeps living only for her son. You are very moral and blessed. Don’t cause suffering for your respected and always revered family. I constantly cry in pain because my children are dead. Don’t make his mother Gautamī, to whom your guru was so dear, become like me. If kings anger their teachers by not being submissive, their family is soon incinerated and everyone connected to them comes to misery.”
The king, Dharma’s Son, supported the queen’s words as glorious, egalitarian, pure, merciful, just, and moral. Nakula and Sahadeva, Yuyudhāna, Dhanañjaya, the All-Attractive son of Devakī, and all the royal ladies agreed.
Dharma’s Son is King Yuddhiṣṭhira, Arjuna’s oldest brother. Nakula and Sahadeva are twin brothers of Arjuna. Yuyudhāna is Arjuna’s best friend and classmate. Dhanañjaya is another name of Arjuna.
Then, in anger, Bhīma said, “It is said that he should be killed for his own good! Without reason or need he uselessly killed sleeping children!”
Bhīma is another brother of Arjuna.
Having heard Bhīma, Draupadī, and the rest, the Four Armed looked upon the face of his friend with a smile and spoke.
Kṛṣṇa looked affectionately upon Arjuna and spoke.
The Beautiful All-Attractive said:
Someone related to our teacher must not be killed, but an aggressor must be killed. Both are true. You must abide by both and also must not break the promise you made to your beloved wife. You must pacify dear Bhīmasena, Pāñcālī, and myself as well.
Pāñcālī is another name for Draupadī, Arjuna’s wife.
Arjuna then suddenly understood Hari’s heart, and so with his sword cut the jewel and hair from the head of the twice-born.
The “twice-born” refers to a brahmana. In this case it refers to the murder, Aśvatthāmā.
Bereft of power and influence due to having killed children, and being deprived of his jewel, he was released and exiled from their camp.
Cutting hair, taking wealth, and putting to exile are fit punishments for those related to Brahmins. Killing or other methods are not to be used.
Overwhelmed with misery, all the Pāṇḍavas accompianied Kṛṣṇā to do what they must for the sake of those who had died.