Today I am sharing some motivational quotes described in Bhagvad Gita ( This post is inspired by article "7 Bhagavad Gita Sayings For A Happy Life" written by 
- It is better to perform your own duties imperfectly than to master the duties of some one else.
- Abandon all attachment to the results of action and attain supreme peace.
- Strive to still your thoughts. Make your mind one-pointed in meditation. The mind is restless and difficult to restrain, but it is subdued by practice.
- Those who eat too much or eat too little, who sleep too much or sleep too little, will not succeed in meditation. But those who are temperate in eating and sleeping work and recreation will come to the end of sorrow through meditation.
- If you perform the sacrifice of doing your duty, you do not have to do anything else. Devoted to duty, man attains perfection.
- Whatever action is performed by a great man, common men follow in his footsteps, and whatever standards he sets by exemplary acts, all the world pursues.
- Free from anger and selfish desire, unified in mind, those who follow the path of yoga and realize the Self are established forever in that supreme state.
- Death is as sure for that which is born, as birth is for that which is dead. Therefore grieve not for what is inevitable.
- Man is made by his belief. As he believes, so he is.
- No purifier equals knowledge, and in time the man of perfect discipline discovers this in his own spirit.
- The power of God is with you at all times; through the activities of mind, senses, breathing, and emotions; and is constantly doing all the work using you as a mere instrument.
These are only some quotes from Bhagvad Gita, you can find many more on internet.
You can check this websites as well for same.
http://www.inspiration.rightattitudes.com/authors/the-bhagavad-gita/
http://buzz.iloveindia.com/50-most-inspiring-quotes-from-the-bhagavad-gita.html