Mythology : : Being a part of the Indian mythology, Vaastu Shastra is also associated with a legend in the Matasya Purana. It was believed that the giant Vaastu Purush surfaced from the sweat of Lord Shiva, while He was fighting with a demon, Andhakasur. Vaastu Purush drank all the blood of the demon, yet his thirst wasn't quenched. Then he underwent a long-term atonement, as a result of which, Lord Shiva granted him a boon - to be the most powerful spirit on the earth. Consequently, the giant began to threaten and wolf down people, and spread terror and agitation. Seeing this, the deities crushed him on the earth and defeated him. They surrounded him from all the directions and sat on him. The Purusha then prayed to Lord Brahma, who gave him a boon that whoever will respect Vaastu Purusha and offer him puja before starting construction of any kind, will enjoy the materialistic comforts and be joyous and contented in that architecture. But those who disrespect Vaastu Purusha or do not offer him puja would be at his mercy and he may bother them in anyway he wanted.