There is a very interesting story about how Yoga came to earth. Lord Shiva was doing his Nataraja dance and Lord Vishnu was watching it. Vishnu gets more and more engrossed in the dance and he forgets his surroundings totally. Adisesha – the thousand headed serpant, on whom Vishnu rests, sees Vishnu immersed in Shiva’s dance. After the dance is over, he asks Vishnu what was the secret to such total concentration and how a common man can learn the same. Vishnu replies that when the object becomes one with the subject, that is Yoga – a total lack of fluctuation of the mind. Adisesha then hears from Vishnu the secrets and is advised to go to Earth and spread the knowledge. Adisesha takes the form of Patanjali and thus he comes to write about the Patanjali Sutras. Ancient depictions of Patanjali have a multi-headed serpent with him.
Interestingly, Patanjali is also credited with bringing to Earth Grammar and Ayurvedha in addition to Yoga. This is explained in the beautiful sloka
Yogena Chittasya, Padena Vaacha, Malam Shareerasya
Cha Vaidyakena Yopa-karothum Pravaram Muninaam,
Patanjaleem pranjalira nato-asmi.
Through Yoga you corrected the mind (Chitta);
through Grammar (Pada) you corrected the talk (vaacha);
through Ayurveda (vaidya) you cured the bad (malam) in the body (shareera).
One who is supreme among Yogis – Patanjali
I bow to you.
Keep up your practice,