Ekdant Ganesh

Once, Lord Parshuram Came to Mount Kailash to have a darshan of Shiva. Since Shiva was sleeping peacefully, Ganesha, who was stationed at the door, stopped Parashurama from going inside. This led to a fight between them. Ganesha caught hold of Parashurama with his trunk and threw him on the earth. Parashuram became unconscious for some time. When he regained consciousness, he threw his axe at Ganesha. Ganesha immediately recognized it as his father’s weapon (which his father had given to Parashurama) and received it with complete humility on one of his teeth. Due to this, one of his teeth broke and only one tooth was left.

According to another story, when Ganesha was asked to write the epic Mahabharata, sage Vyas asked him to break his tooth and use it as a pen. Ganesha happily broke his tooth and made a pen from it. From this, we learn that great sacrifice may be required to attain knowledge.