[38] The vajra was originally the thunderbolt weapon of Indra, the Indian Zeus. The Buddhists changed it to the symbol of highest spiritual power 'the Adamantine Sceptre' which is irresistible and invincible. The double or crossed vajra (Skt. visva-vajra) symbolises immutability, and is hence used in designs of thrones and seats, inscribed on bases of statues, pillars, foundations of houses, anywhere where permanence is desired.