Lord Narayana’s discus, Sudarsana, plays a major role in protecting His devotees. Hiranyakasipu wanted Prahlada to acknowledge his (Hiranyakasipu’s) superiority over everyone, including the Lord Himself. This was something Prahlada refused to do. So Hiranyakasipu decided to frighten the boy so much that he would, in his fear, admit what he had earlier refused to admit.
So Hiranyakasipu sent for Viprachiti, who knew magical tricks and could create illusions to frighten Prahlada. But the illusory tricks that Viprachiti conjured up were all got rid of by Sudarsana, said V.S. Karunakarachariar in a discourse. In the Mahabharata, Duryodhana was mortally wounded. His army had been almost completely wiped out. Aswattama, son of Drona, had always wanted to be the commander of the Kaurava army. Now he approached Duryodhana and asked if he could head what was left of the army. Only three people were left, including Aswattama himself. Duryodhana granted Aswattama his wish. As Aswattama contemplated how he could kill the Pandavas, he saw owls boldly pecking at crows that had retired to their nests for the night. The boldness of the owls was because they could see well in the dark. Aswattama, thinking that there was a message in this for him, decided to attack the Pandavas at night. But Krishna moved the Pandavas away from their tent, so that Aswattama ended up killing all five sons of Draupadi.
But the Pandava lineage would have not come to an end even with these deaths, for Uttara, Abhimanyu’s wife was expecting a child. So Aswattama sent an arrow and burnt her foetus. But Krishna entered her womb and stroked the foetus with His discus. This brought the charred foetus to life.
