Mahabharata 3.33.52

3.33.52

vyasanaṃ vāsya kāṅkṣeta vināśaṃ vā yudhiṣṭhira |
api sindhorgirervāpi kiṃ punarmartyadharmiṇaḥ || 52 ||

When the man of intelligence seeth his enemy superior to him in many qualities, he should seek the accomplishment of his purposes by means, of the arts of conciliation and proper appliances. He should also wish evil unto his foe and his banishment. Without speaking of mortal man, if his foe were even the ocean or the hills, he should be guided by such motives. A person by his activity in searching for the holes of his enemies, dischargeth his debt to himself as also to his friends. No man should ever disparage himself for the man that disparageth himself never earneth high prosperity. O Bharata, success in this world is attainable on such conditions! In fact, success in the World is said to depend on acting according to time and circumstances. My father formerly kept a learned Brahmana with him. O bull of the Bharata race, he said all this unto my father. Indeed, these instructions as to duty, uttered by Vrihaspati himself, were first taught to my brothers. It was from them that I heard these afterwards while in my father's house. And, O Yudhishthira, while at intervals of business, I went out (of the inner apartments) and sat on the lap of my father, that learned Brahmana used to recite unto me these truths, sweetly consoling me therewith!"