Mahabharata 12.112.63

12.112.63

tasmātpratyakṣadṛṣṭo'pi yuktamarthaḥ parīkṣitum |
parīkṣya jñāpayanhyarthānna paścātparitapyate || 63 ||

Let this fact be well considered (in finding out the thief). Wicked persons sometimes put on the semblance of the good, and they that are good sometimes wear the semblance of the wicked. Diverse kinds of aspect are noticeable in creatures. It is, therefore, necessary to examine which is which. The firmament seems to be like the solid base of a vessel. The fire-fly seems to be like the actual spark of fire. In reality, however, the sky has no base and there is no fire in the fire-fly. You see, there is necessity. therefore, for scrutiny in respect of even such things as are addressed to the eye. If a person ascertains everything after scrutiny, he is never called upon to indulge in any kind of regret afterwards. It is not at all difficult, O son, for a master to put his servant to death. Forgiveness, however, in persons possessed of power, is always praiseworthy and productive of renown. Thou hadst made the jackal thy first minister. In consequence of that act, thou hadst earned great fame among all neighbouring chiefs. A good minister cannot be obtained easily. The jackal is thy well-wisher. Let him, therefore, be supported.