"You have the right to perform your prescribed duties, but you are not entitled to the fruits of your actions." - Bhagavad Gita 2.47
"A person can rise through the efforts of his own mind; he can also degrade himself, again by his own mind. Because of his mind, he can either be his friend or his enemy." - Bhagavad Gita 6.5 -
Perform your obligatory duty, because action is indeed better than inaction." - Bhagavad Gita 3.8 -
"One who sees inaction in action and action in inaction is intelligent among men, and he is in the transcendental position, although engaged in all kinds of work." - Bhagavad Gita 4.18"
"The wise man lets go of all results, whether good or bad, and is focused on the action alone." - Bhagavad Gita 2.50