In plain words
what is it like? Aśvatthāmā cut the throats of Draupadī's five sons as they slept in the dark, and came away. They were children who knew nothing at all. He cut the throats of mere tender children. At last Arjuna caught Aśvatthāmā and brought him. He brought him before Draupadī. Think well how great forbearance is.
Our husbands, all of them, in days gone by, the loosing of the arrow and its recall and every science of arms learnt from Droṇācārya; you are Droṇa in the form of his son; in your heart, with not the least touch of compassion, is it right to cut down the sons of his disciples?
Seeing Draupadī forgiving in her forbearance, Bhīma grew angry.
She is not angry that he seized her sons and killed them; this child-killer she tells us to let go: Draupadī is a simpleton. Is this fellow a brāhmin? Why let him go? Kill him, you; if you will not kill him, with my fist's blow I will split his head open; watch, all of you.
Draupadī went and took hold of their feet.
One who is afraid, one in misery and pain, one who in sleep has lost himself, one who in his ease has drunk liquor, one who, broken, has fled, one of a meek and simple nature, one who cries “Save me,” beating his mouth, and women: to kill them is not Dharma, Arjuna.
This is not just. If you kill this Aśvatthāmā, this Aśvatthāmā's mother too will grieve as much as I am grieving now that my children are gone, will she not? My children are dead in any case. There is no escaping the sorrow. Why kill him and bring sorrow to his mother? This is forbearance as it should be. We must recognise the Satya that as our own pains are, so are the pains of the one before us. Aśvatthāmā's mother will grieve at the loss of that son as much as I grieve at the loss of my sons. “So do not kill Aśvatthāmā,” she pleaded with Bhīma and Arjuna. In these times would any mother keep such forbearance, such patience? She, none other,