King Rugmangada, a devotee of God Vishnu, strictly observed the Ekadasi fasting considered sacred. He accumulated so much merit that the gods became jealous and decided to test Rugmangada’s devotion. They depute the celestial enchantress, Mohini, to him. Besotted by her charm, on his request Mohini agrees to stay with the king as his paramour. But only as long as he grants all her wishes and promises not to come against it. One day he resists her. Mohini reminds him of his vow and agrees to release the King from his promise if he beheads his own son, Dharmangadan. Rugmangada agrees to slay his son rather than stop his prayers. As the King raises his sword to behead his own son, Lord Vishnu, recognizing the King’s devotion to him, stops the sword. The story shows the great benefits which were promised to devotees of Vishnu who observed the Ekadasi fast.