Trishula is a divine weapon, and it also represents the “Victory Symbol”, and it is used by Lord Shiva, who holds it in his hands. Trishula was mentioned in ancient Puranas, Vedas and other holy texts, and it is considered as a very sacred weapon since it belongs to Lord Shiva.
In some pictures, we can see Mata Parvati who holds a Trishula, and she used it during the time of killing of the demons. Similarly Lord Vinayaka and Muruga also used it while fighting with the demons. Lord Shiva used it at the time of slaying of the demons.
Once, Lord Shiva protected his beloved devotee, Banasura, the great grandson of Prahlada, with his Trishula, when Banasura was attacked by Lord Krishna. As per legend, once the divine architect, Lord Vishwakarma created the trishula and gave it to Lord Shiva. Trishula is mentioned in Buddhism.
As per the great epic Ramayana, once the demon king Lavanasura had performed severe meditation on Lord Shiva, and got the Trishula from Lord Shiva as a boon from him. Later Shatrughna had easily killed Lavanasura, when Lavanasura didn’t possess the weapon in his hand. Lord Indra received the divine Trishula from Lord Shiva during his fight with the demons.
Trishula forms part and parcel of Lord Shiva, it is the divine weapon, and it removed the fears of the Devas, and also gave victory for them. Trishula is a powerful weapon and it can be compared with other divine Astras like Indrastra, Vaivastra, Agniastra and Varunastra. Trishula can be commonly found in front of most of the Amman temples, and also in the temples of Guardian gods like, Ayyanar, Muneeswaran and Karuppanaswamy.
It is a holy thing, which represents the Shiva aspect, and worshipping the Trishula is similar to worshipping Lord Shiva.