"Karmanye Vadhikaraste, Ma phaleshou kada chana,

Ma Karma Phala Hetur Bhurmatey Sangostva Akarmani"

"कर्मणयेवाधिकारस्ते मा फलेषु कदाचन।

मा कर्मफलहेतुर्भूर्मा ते सङ्गोऽस्त्वकर्मणि।  "

Above  verse is from the  Shri Bhagawad Gita, where Arjuna was not willing to fight the Epic war of Mahabhaarat and Lord Shri Krishna explains to him to perform his duties.

Translation :

"You have a right to perform your prescribed  action, but you are not entitled to the fruits of  your action.

Never consider yourself the cause of the results of your activities,and never be associated to not doing your duty."