There is a story in Narada Purana which narrates the greatness of Tulsi leaves and how it saved a man from certain death. There lived a man named Madhava who never performed any worship in his entire life and neither did he do any good deeds. Madhava cultivated his land and kept cows for a living. Every day, be brought grass for his cows from his field. One day, while collecting grass for his cows, he cut some Tulsi leaves along with the grass. He was destined to die that evening and a snake came slithering towards him to bit him and end his life at the predetermined time. But the snake was unable to bite him as he had Tulsi leaves in his hands. The man picked up the bundle of grass along with the Tulsi leaves and placed the bundle on his head and returned home. The snake hid in the bundle, hoping to bite him when he is not contact with the Tulsi leaves. Neighbor of Madhava was Madhusudana, a pious man. He was able to see the snake in the grass bundle and through his yogic powers