The word “Yoga” has been used in Vedas, Upanishads, Gita and mythological scriptures etc. since ancient times. It is a very important terminology in Indian 'Darshan'. It has been used widely in our classics from deep devotion and meeting with the internal soul to work. According to Saint Patanjali, spiritual instructor of Yoga Darshan, "Yoga is obstruction of conditions. Facts, transposition, alternative, sleep and memory, when these five conditions attain concentration in the mind due to resources like practice and asceticism and get situated in the soul, then it is Yoga.
According to Saint Vyas, "Yoga is deep meditation". According to classical grammar, the word 'Yoga' is derived from the deep knowledge of connecting humors of the body. It has been described in Dhatupath by sage Panini in the chapter Divadigan as connecting with deep meditation, in Rudhiradigan as connecting with Yoga, and in Churadigan as connecting with patience, in these meanings the word connecting humors is used. In short, we can say that devoting ourselves with patience and connecting the individual soul with the supreme soul and attaining the happiness of deep meditation is Yoga.
According to the conceptions of the above mentioned sages, Yoga implies the association with the supreme soul, which is attained between the central point of individual and the ultimate souls. When a person f's mentally affected by complete understanding and is filled with the feeling of asceticism, he goes much above the momentary happiness, conditions and associates with the powerful soul. There are five conditions of the soul— clarity, stupidity, confusion, concentration and highest contemplation. In the first three conditions, Yoga or deep meditation does not take place. In the conditions of concentration, when the five obstacles i.e., ignorance, attachment, hatred, affection are caused due to ignorance, and the bonds of karma become weak then contemplation accompanied by reasoning, thinking, happiness and pride takes place. In this case, highest contemplation takes place which is not associated with any idol, thing or meaning.
In the Indian mythology, Gita has a special place. The modern Indian sages have propagated Gita all over the world. The Lord of Yoga, Shri Krishna has been referred in Gita with various meanings.
To be contended and remain stable in conditions of favorable- unfavorable, success-failure, accomplishment-non-accomplishment, victory-loss is called Yoga. To get inspired by internal inspiration and look into the soul with clear mind and work skillfully has been considered Yoga in Gita.