In Yoga, Lord Shiva is considered the Adi Yogi and the Adi Guru. He is the foremost among the yogis and the first teacher of the science of Yoga. He is an ideal renunciate and an ideal householder. He is depicted as sitting in lotus pose on mount Kailas, in deep samadhi, unmoved by the events of the universe. His body is smeared with sacred ash. In his hair is the crescent moon symbolizing mystical vision and knowledge. The serpent coiled around his neck symbolizes the mysterious kundalini energy present in all of us. The river Ganges cascades from the crown of his head symbolizing perpetual purification, which he bestows upon his devotees. He is the three-eyed one or Trilochana as he has the third eye or the eye of wisdom in the centre of the forehead. He is described as the “blue-throated” or Neelakanta. His trident represents the three gunas or qualities of Nature, namely tamas, rajas, and sattva. He is Yogeshwara, the lord of Yoga; Maheshwara, the Great God and Bhuteshwara, the lord of the five elements from which the universe is created.
Shiva is considered to be with form and without form. The Manifest and Unmanifest. Languages cannot describe the void, the emptiness, the nothingness, the shoonya that he is. He is the Absolute, Nirvikalpa Samadhi, beyond Consciousness and yet Supreme Consciousness. Shiva is described as formless and is worshipped as the Siva Linga and is considered the ultimate reality itself. Even though the formless cannot be given a form, the oval-shaped, ellipsoid Shiva Linga is said to be the first form taken during creation. Shiva brought this possibility that a human being need not be contained in the defined limitations. There is a way to be contained in physicality but not to belong to it. There is a way to inhabit the body but never become the body. There is a way to use your mind in the highest possible way but still, never know the miseries of the mind. Whatever dimension of existence you are in right now, you can go beyond that - there is another way to live.
Shiva & Shakti
Shiva is considered the supreme consciousness in which the play of creation happens in the form of Shakti. Shiva and Shakti are inseparable, just as the creation cannot be separated from the creator. The whole of creation is described as Shiva Tandava or the dance of Shiva. Our Prostrations to the formless One, who has taken a form out of Compassion. Shiva and Shakti are in Union in a Self-Realized/Enlightened one. They are depicted as Ardhanarishwara (Androgynous).
Ardhanarishvara is one of the 64 manifestations of Parashiva, the aspect of Lord Shiva, who is Absolute, beyond all human comprehension and is hence considered the Nirguna Brahman (the Supreme One, who is beyond attributes). Since Ardhanarishvara represents the perfect synthesis of male and female forms, it also embodies the Prakriti and the Purusha, the feminine and masculine energies of the cosmos and also illustrates how Shakti, the Sacred Feminine, is inseparable from Shiva, the male principle of God. This form also symbolizes the all-pervasive, all-enduring nature of Lord Shiva. The concept of Ardhanarishvara indicates that "totality lies beyond duality" and the essentially equal nature of both the masculine and feminine energies. It talks about both being part of the Supreme Being, being two equal parts, making the whole.