Shiva is the god of the yogis, self-controlled and celibate, while at the same time a lover of his spouse (shakti). Lord Shiva is the destroyer of the world, following Brahma the creator and Vishnu the preserver, after which Brahma again creates the world and so on. Shiva is responsible for change both in the form of death and destruction and in the positive sense of destroying the ego, the false identification with the form. This also includes the shedding of old habits and attachments.
All that has a beginning by necessity must have an end. In destruction, truly nothing is destroyed but the illusion of individuality. Thus the power of destruction associated with Lord Shiva has great purifying power, both on a more personal level when problems make us see reality more clearly, as on a more universal level. Destruction opens the path for a new creation of the universe, a new opportunity for the beauty and drama of universal illusion to unfold. As Satyam, Shivam, Sundaram or Truth, Goodness and Beauty, Shiva represents the most essential goodness.
While of course many hindu deities are associated with different paths of yoga and meditation, in Shiva the art of meditation takes its most absolute form. In meditation, not only mind is stopped, everything is dropped. In deep meditation or samadhi, even the object of the meditation (like a mantra) is transformed into its formless essence, which is the essence of everything and everyone. Thus Shiva stands for letting go of everything in the world of forms. The path of Lord Shiva is the path of the ascetic yogi.
Shiva is referred to as 'the good one' or the 'auspicious one'. Shiva - Rudra is considered to be the destroyer of evil and sorrow. Shiva - Shankara is the doer of good. Shiva is 'tri netra' or three eyed, and is 'neela kantha' - blue necked (having consumed poison to save the world from destruction. Shiva - Nataraja is the Divine Cosmic Dancer. Shiva - Ardhanareeswara is both man and woman.
He is both static and dynamic and is both creator and destroyer. He is the oldest and the youngest, he is the eternal youth as well as the infant. He is the source of fertility in all living beings. He has gentle as well as fierce forms. Shiva is the greatest of renouncers as well as the ideal lover. He destroyes evil and protects good. He bestows prosperity on worshipers although he is austere. He is omnipresent and resides in everyone as pure consciousness.