Mbh 13.8.2c

Yet when angry they are like snakes of virulent poison. They should, for these reasons, be always waited upon and served with reverence and humility. One should, O Yudhishthira, always fear these two, viz., Energy and Penances. Both these should be avoided or kept at a distance. The effects of both are speedy. There is the superiority, however, of Penances, viz., that Brahmanas endued with Penances, O monarch, can, if angry, slay the object of their wrath (regardless of the measure of Energy with which that object may be endued). Energy and Penances, each of the largest measure, become neutralised if applied against a Brahmana that has conquered wrath. If the two,--that is, Energy and Penances,--be set against each other, then destruction would overtake both but not destruction without a remnant, for while Energy, applied against Penances, is sure to be destroyed without leaving a remnant. Penances applied against Energy cannot be destroyed completely.[13] As the herdsman, stick in hand, protects the herd, even so should the Kshatriya always protect the Vedas and the Brahmanas. Indeed, the Kshatriya should protect all righteous Brahmanas even as a sire protects his sons. He should always have his eye upon the house of the Brahmanas for seeing that their means of subsistence may not be wanting."'"