Patanjali mentions four principles to be followed by a practitioner of yoga in his or her daily life. In the beginning, it is hard to follow all this but by practicing yoga and with the grace of Guru, a disciple attains and starts practicing in daily life. Patanjali mentions students of yoga should not misunderstand the concept of yoga that a yogi should live in the forest or caves only, but infect he or she should also practice yoga in society to be a good human being. The yoga student should follow the four principles of yoga for well beings and happiness for him and to create brotherhood and peace among human beings.

Maitri

A person, who follows the path of yoga, should consider all human beings as friend and treat them accordingly. As long as we are full of greed, selfishness, and narrow minded and full of ego, will never treat other as our good friends. Therefore once we remove them by practicing yoga then true nature of soul reflects in daily routine of our life like true friendship, treats all other human beings as friends and love to all.

Karuna

Compassion.  A person, who practices yoga should not only run after happiness but also show his compassion to all creators. Compassion is very closely related to the true love. Those who are suffering from illness, poor, weak, and ignorant, a yogi should show them his compassion and help them as much as possible to bring them back to normal life. Great sages like Swami Dayananda despite a great yogi save millions of people and impart the knowledge to them, in order to save them from misery. Dayananda also worked hard to uplift the position of the woman in India during nineteenth century.

Mudita

God has given us a free technique to control the emotions and overcome several diseases by just smiling and creating happy environment around us. Therefore, every human being should learn to smile and laugh while practicing yoga. Stress, mentally upset, and anger can be easily avoided if we learn to practice Hasya Yoga, means laugh for three minutes every morning so that we live cheerful all the day. This free gift is given only to the human beings and not to other creatures. Therefore, do smile and make others smile by practicing yoga. A real yogi uses smile as a weapon to remove suffering of people.

Upeksa

Upeksa means avoid the wicked person and do not indulge in association of bad habits and people like grumblers, criminals, and drug users. A yogi should avoid the wicked and not follow the path of confrontation or fight. A common person should at least forgive a person 3 times but a yogi should forgive a person at least 99 times like Krishna of Mahabharata forgave his uncle 99 times. But when he crossed the limits then he punished him. Krishna was a great yogi himself and used to practice Sudarsana Kriya, a part of breathing exercise and by this practice, he developed a weapon called Sudarsana Cakra.