The purpose of your life is experiencing the desire which brought you here.
We take birth because of desire and for a lifetime we remain prisoners of this desire, forgetting the purpose of our life and taking the downward spiral by entangling ourselves in the various attractions of the physical world namely, relationships, career — the web of maya. The purpose of your life is experiencing the desire which brought you here. And desire is unending, as it starts the cycle of karma until the soul decides that the purpose is over and it needs to go back home. You have to pay back for your every karma. While it’s fine to experience and enjoy the pleasures, it is also important to remember the purpose of your life and that for every pleasure you indulge in, there comes an associated pain. That maintains the balance in this creation. We are limited with our senses and the limitations of our mind cannot comprehend either our life’s purpose or the ways to achieve it; we just carry on with our lives until we meet a guru, who defines our path and its purpose and gives the means to achieve it too.
Lord Ram was just 14 when Maharishi Vishwamitra came to take him away to annihilate the most dreaded of the demons of those times. Dashrath blinded by the veil of maya was aghast with the idea, but his guru Rishi Vashishtha assured him of the great victory his son is going to mark when the grace of guru Vishwamitra falls upon him. Lord Ram, an incarnation of Lord Vishnu, bowed at the feet of his guru and received the grace. The grace of a guru is the collected tapas performed by the guru himself, which he grants to his shishya. It is said that Maharishi Vishwamitra was alone capable of slaying all the demons of the earth, including Ravan, but he chose Ram, to give all his weapons and their energies.
In this day and age, demons like Ravan, Hiranyakashyap, Kansa do not exist in the bodies but they do exist as energies. By the force of their evil, they easily get into human beings, and take the guise of gurus. It is imperative to safeguard yourself. The ways recommended are the principles of Ashtanga Yoga in general, and the five yamas in particular are satya (truth), asteya (non-stealing), aparigraha (non-collection), ahimsa (non-violence) and brahmacharya (celibacy).
In Kalyug, any person practising the yamas has the capacity to become a guru. And exalted soul not practising them can become the embodiment of Ravan.