In Hinduism, it’s believed that earth is resting on the head of a giant snake known as Sheshanaga. So as per the legend, Sheshanaga is the king of all snakes and has a thousand heads and is supporting the whole universe on his many heads. It is also called as ‘Ananta-Shesha‘ meaning endless snake. Another name for it is ‘Adi-Shesha‘ meaning the first snake. So Sheshanaga has existed from the beginning of the universe and is endless in nature.
All these facts and the legend looks foolish at the first instance but it has a deep symbolic meaning like most of the stories mentioned in the Puranas or other Hindu scriptures.
Significance of legend – Earth is supported on the head of Sheshanaga:
1. Kundalini Energy and Sahasrara Chakra:
In mysticism, to represent the kundalini energy, the symbolism of snake is very often used. The snake is used to represent kundalini shakti because when the need arises then it can raise its hood and stand vertically.
According to Hindus, there are seven main chakras in the body. Kundalini shakti resides at the Muladhara chakra (root chakra).When the kundalini energy is awakened and reaches to the Sahasrara chakra then the person becomes awakened. The kundalini shakti has to be awakened so that it rises vertically and passes through all the seven chakras and come at Sahasrara Chakra (Crown Chakra).
Now you can start seeing the similarity between Sheshanaga who is considered as the king of snakes and has 1000 heads and Sahasrara chakra, which when fully opened is described as a lotus flower with 1,000 petals of different colors. When a person become awakened then he becomes like a king because he has got mastery over his inner senses.
The legend simply indicates that the world is resting on the good deeds and power of dharma spread by enlightened masters like Buddha, Mahavira, Kabir, Ramakrishna, Meera, Gorakh, Christ, Nanak, Milarepa. E.g. Because of Buddha and Mahavira many people took the path of peace, meditation, and non-violence. Otherwise, there would have been more violence and fights in the world.
The enlightened masters have shown us the path of truth, compassion, love, universal brotherhood, peace, and non-violence. Without their presence and their teachings, the mankind would have been more barbaric in nature and would have probably destroyed the earth by now. In the current nuclear era, one thing which we need the most is an enlightened master who can start a new era of peace, love and compassion.
2. “Shesha” – Sheshanaga is sometimes simply called as ‘Shesha’. In the Sanskrit language, the word Shesha translated to “remainder” – that which remains when all else ceases to exist. In Hinduism, it is believed that dharma (righteousness) will always win in the end and will always remain. Darkness is the absence of light. When the light comes then darkness disappear on its own. Lord Krishna has said in Bhagavad Gita that whenever the demonic forces will gain power, then Lord Vishnu will take an avatar to bring back the order in the world. So there will be the victory of dharma in the end.
In the Hindu holy scriptures, Lord Vishnu is often mentioned as resting on Sheshanaga. Sheshanaga is considered as a devotee of Vishnu. The two most important incarnation of Lord Vishnu are Lord Rama and Lord Krishna. In these two incarnations, Sheshanaga also took birth as Laxmana in Ramayana and Balarama in Mahabharata to help the Lord Vishnu in the divine task of removing the Adharma (or demonic energy) from the earth.
3. Sheshanaga – As said before ‘Shesha’ means which remains in the end and ‘Naga’ is Hindi word for snake. Serpent power is used to represent energy in mysticism. So the word ‘Sheshanaga’ (Shesha + Naga) translates to the “energy which will remain in the end“.
Sheshanaga is usually shown with a massive form that floats in the ocean of milk (Sheer Sagar in Hindi) and it also form the bed on which Lord Vishnu lies. Now, what is this ocean of milk and the energy which will always remain in the end. In scientific term you can call it milky way galaxy (Ocean of milk) or our vast universe. This milk way or vast universe was always there and will always remain. If you talk in terms of science than everything is energy. This whole world is a play of energy or at molecule level play of electrons, neutrons and protons.
The Quantum physics agrees with many of Hindu stories. To know these things in further detail, you will need to study modern findings of quantum physics and how they are related with the concept of Shiva (Consciousness) and Shakti (Energy).