Mbh 12.15.2e

All our acts, without doubt, are dependent on wealth; that wealth again is dependent on chastisement. Behold, therefore, the importance of chastisement. Duties have been declared for only the maintenance of the relations of the world. There are two things here, viz., abstention from injury and injury prompted by righteous motives. Of these two, that is superior by which righteousness may be acquired.[40] There is no act that is wholly meritorious, nor any that is wholly wicked. Right or wrong, in all acts, something of both is seen. Subjecting animals to castration, their horns again are cut off. They are then made to bear weights, are tethered, and chastised. In this world that is unsubstantial and rotten with abuses and rendered painful, O monarch, do thou practise the ancient customs of men, following the rules and analogies cited above. Perform sacrifices, give alms, protect thy subjects, and practise righteousness. Slay thy foes, O son of Kunti, and protect thy friends. Let no cheerlessness be thine, O king, while slaying foes. He that does it, O Bharata, does not incur the slightest sin. He that takes up a weapon and slays an armed foe advancing against him, does not incur the sin of killing a foetus, for it is the wrath of the advancing foe that provokes the wrath of the slayer. The inner soul of every creature is incapable of being slain. When the soul is incapable of being slain, how then can one be slain by another? As a person enters a new house, even so a creature enters successive bodies. Abandoning forms that are worn out, a creature acquires new forms. People capable of seeing the truth regard this transformation to be death."'"