Ashwatthama was the son of Dronacharya and Kripi. Drona did many years of severe penance to please Lord Shiva in order to obtain a son who possesses the same valiance as Lord Shiva. We all know that Ashwathama is one of the Chiranjivis. Ashvathama was born with a gem on his forehead which gives him power over all living beings lower than humans; it protects him from hunger, thirst, and fatigue. Though an expert in warfare, Dronacharya lived the simple life of a Brahmin, with little money or property.
Miserable Childhood of Ashwathama
As a result, Ashvatthama had a difficult childhood, with his family unable to even afford milk. Wanting to provide a better life for his family, Drona goes to the Panchal Kingdom to seek aid from his former classmate and friend, Drupada. However, Drupada rebukes the friendship, claiming a king and a beggar cannot be friends, humiliating Drona.
After this incident, and seeing the plight of Drona, Kripacharya invites Drona to Hastinapur. There, he comes upon the attention of his co-disciple Bhishma. Thus, Dronacharya becomes the guru of both Pandavas and Kauravas in Hastinapur. Ashwatthama was trained in the art of warfare along with them.
Invoking of Brahmsheer Astra
When Ashwatthama attacked the Pandav Army camp at night and killed many warriors, including Shikhandi, Yudhamanyu, Uttamaujas. Then, Pandavs and Lord Krishna chased Ashwathama. To save himself from the wrath of Pandavs and Krishna, he invoked Brahmasheer Astra. He plucked out a blade of grass and started chanting the mantra in order to invoke the Brahmasheer Astra. The grass which was used by Ashwathama was not a normal grass.
The Mystical Grass
That grass is known as Darbha Grass. Rigveda speaks about this type of grass. In Rigveda, it is mentioned as Desmostachya Bipinnata. Ashwathama used this grass due to one of its unique features. That feature was its capability to block almost any kind of radiation. Today scientists have experimentally proved that Drabha grass can block almost any kind of radiation including X-rays, gamma rays, cosmic rays, etc.
During the process of invoking Brahmsheer Astra from Brahmalok, a lot of cosmic radiation is liberated. Aswathama used Darbha Grass to protect himself from cosmic and other intergalactic radiation involved during the process of invoking the Brahmsheer weapon. Brahmsheer Astra is the most powerful weapon as per Hindu Vedic texts. Even Brahmastra is like a small cracker in front of Brahmsheer Astra. This Astra has the capability to liberate even the parallel universe. This was invoked by chanting a specific mantra at a particular frequency. The bow acts as a frequency selector who has the capability to send the Bijaksharas of the mantra chanted by the warrior at different frequencies to the lokas where the Astra actually exists.
The issue with the Ashwathama was that although he knew how to invoke the Brahmsheer Astra but he was not able to handle and control the power of the Astra. Therefore he used the Darbha grass to protect himself from the cosmic radiation in the whole process.
On the other hand, Arjun was capable to handle the power of the Astra and even had the capability to take it back. Due to this reason, in the bow war between Arjun and Ashwathama. Arjun was able to take the Brahmsheera Astra back but on the other hand, Ashwatha was only able to change its direction towards the womb of Uttara.
Significance of Drabha Grass
Since Vedic age, Darbha grass is treated as a sacred plant and according to early Buddhist accounts, it was the material used by Buddha for his meditation seat when he attained enlightenment under the Bodhi tree.
Darbha or Kusha grass is specifically recommended by Lord Krishna in the Bhagavad Gita as part of the ideal seat for meditation. It is believed to block energy generated during meditation from being discharged through our body into the ground.
Darbha has the highest value in conducting the phonetic vibrations through its tip. Priests in India dip this tip in water and sprinkle all over the house or temple to purify the place.
During Fire-ritual, Darbha is placed on all four sides of the fire to help block all negative radiations. During eclipses, Darbha is placed on vessels containing water and food, so that the negative effect of rays from eclipse does not spoil them.