After all his attempts failed, Vishwamitra turned to Vashishtha, seeking the secret of his power.
"My abilities arise from within," Vashishtha replied. "They are the result of my meditation and unwavering adherence to discipline."
Reflecting on his defeat, Vishwamitra thought, Despite being a mighty king, I was overcome by a forest-dwelling sage. I, too, must attain such great power. Determined, he instructed his son to oversee the administration of his kingdom. Then, he relinquished all his wealth and luxuries and retreated to the forest. To earn the grace of Lord Shiva, he practiced intense penance and other forms of divine worship with fervent devotion. When Shiva appeared before him, Vishwamitra requested powers akin to Vashishtha’s, particularly the invincible Brahmastra, to ensure his victory. Shiva granted his wishes.
Soon after, Vishwamitra launched an attack on Vashishtha. Yet, Vashishtha, calm and untroubled, stationed his disciples at the entrance of his ashram and withdrew to meditate. With steadfast resolve, the students managed to block and neutralize all of Vishwamitra’s weapons, including the formidable Brahmastra.