A diamond is so hard that nothing can break it except the horn of a sheep and the shell of a tortoise. Large birds cannot snap the branch of a large tree called nyagrodha though the wren, a small bird said to nest on the eyelashes of mosquitoes, can. The evil karma of ordinary people like us, is as hard as a diamond and as big as nyagrodha. The daimoku of the Lotus Sutra, on the contrary, can easily break and snap the karma of ordinary people, like the horn of a sheep and the beak of a wren.
Hokke Daimoku Shō, Treatise on the Daimoku of the Lotus Sūtra