It is important to understand the various limbs of Yoga. Unless one understands these limbs of spiritual practice, one shall not be sure or ascertained about the proper spiritual discipline that one should take up. Understanding the nature of mind and its relation to the spirit as well as the world is important. Understanding Jnana and Bhakti in that context becomes vital.
The story of sages cannot be complete without the story of Lord Shiva, the original sage, the master of all sages. He is the epitome of the ideal Guru. If a guru has to cultivate himself, as a giver of knowledge, then he needs to be the humble follower of Lord Shiva. Lord Shiva sets the example , a prelude to the way gurus should set precedent.