Broncho Billy, a young clergyman, is struck on the head and left for dead by his partner, just after they have struck it rich on a mining claim. He is found by a young Indian girl and taken to the Indian camp where he is nursed back to health. During his convalescence he teaches the girl the commandment, "Thou Shalt Not Kill," and the motto, "Forgive and Forget." Another Indian girl asks him to write out the mottoes for her. Broncho grants her request, whereupon the first girl tries to kill her. Broncho frustrates the attempt by showing her the commandment written on the slate. The clergyman's partner is captured by the Indians and brought to the camp. The chief orders that he be killed, but the clergyman saves his life. The prospector comes to thank him and Broncho recognizes his partner. Crazed by rage he attempts to kill him, but the Indian girl shows him the commandment in his own writing. He obeys it. His partner makes restitution.