“If the radiance of a thousand suns were to burst at once into the sky, that would be like the splendor of the mighty one. Now, I have become Death, the destroyer of worlds.” (Bhagavad Gita).
As described in the sastra, a Brahmastra is an astra, or celestial weapon created by Lord Brahma. It is sometimes known as the Brahma Astra (astra referring to ‘missile weapon’). As described in a number of the Puranas, Brahmastra is considered to be the very deadliest of weapons. When a Brahmastra is discharged, neither a counterattack nor a defense of any kind can stop it. In ancient Sanskrit writings, the Brahmastra was a weapon created by Brahma,along with its more powerful versions like Brahmashirsha astra and Brahmanda astra.Brahmastra and Brahmashirsha astra are said to be mythical equivalent of modern day atomic weapons, nuclear and thermonuclear bombs respectively because the weapon was also believed to cause severe environmental damage. The land where the weapon was used became barren and all life in and around that area ceased to exist, as both women and men became infertile. There was also a severe decrease in rainfall with the land developing cracks, like in a drought.
Since Brahma is considered the Creator in Sanatana Dharma, it is believed by Hindus that Brahmastra was created by him for the purpose of upholding Dharma and Satya, to be used by anyone who wished to destroy an enemy who would also happen to be a part of his (Brahma’s) creation. The target, when hit by Brahmastra, would be utterly destroyed. Brahma had created a weapon even more powerful than the Brahmastra, called the Brahmashira. The Brahmashira was never used in war, as it was four times powerful than the Brahmastra, i.e Fourth power square, as the name suggests, since Brahma has Four Heads. Only Arjuna and Ashwatthama possessed the knowledge to summon the Brahmashira.
There are numerous instances within Sanskrit scriptures where the Brahmastra is used or its use is threatened, including:
Vishvamitra used it against Vasishta, but the Brahmastra was swallowed by Brahmadanda, Lord Brahma’s countermeasure against the Brahmastra.
In the Ramayana a Brahmastra is used by Shri Rama as the “final blow” against Rakshasa Ravana during their battle in Lanka. Also, Indrajit used Brahmastra against Hanuman when he was destroying tha Ashok Vatika after meeting Sita. Lakshmana (Shri Rama’s younger brother) also tried to use it with Indrajit in the same battle, but Rama stopped him from using the weapon saying, “his use of the Brahamastra was not justified, nor would it benefit mankind.”
Prior to the Epic war of the war of the Mahabharata, Karna was planning to use the Brahmastra to fight Arjuna, but because of Parasurama’s curse he was unable to do so.
The confrontation of Arjuna and Ashwatthama in Mahabharata, where Arjuna retracts his weapon as ordered, but Ashwatthama, unable to do so, instead sends it to attack Arjuna’s unborn grandson, Parikshit, who is subsequently saved by Krishna.
The confrontation of Arjuna and Ashwatthama is also said to have involved the four square more destructive weapon, the Brahmashira. In this version Ashwatthama did not have his bow and arrow near him when he was confronted by Arjuna. So he took a piece of straw and after silently invoking the proper phrase he threw the straw at Arjuna, which carried the power of the Brahmashiras. In response, Arjuna also invoked the Brahmashira to counter Ashwatthama’s, but the collision of two Brahmashiras would have destroyed the universe, so Vyasdev came between the two Brahmashiras, preventing their collision. Arjuna called back his Brahmashira, but Aswathama did not know how to do this, so he commanded his weapon to attack the unborn grandchild of Arjuna (Parikshit)