I am the good shepherd (egw eimi o poimhn o kalo). Note repetition of the article, "the shepherd the good one." Takes up the metaphor of verses Romans 2 . Vulgate pastor bonus. Philo calls his good shepherd agaqo, but kalo calls attention to the beauty in character and service like "good stewards" ( 1 Peter 4:10 ), "a good minister of Christ Jesus" ( 1 Timothy 4:6 ). Often both adjectives appear together in the ancient Greek as once in the New Testament ( Luke 8:15 ). "Beauty is as beauty does." That is kalo. Layeth down his life for his sheep (thn psuchn autou tiqhsin uper twn probatwn). For illustration see 1 Samuel 17:35 (David's experience) and Isaiah 31:4 . Dods quotes Xenophon (Mem. ii. 7, 14) who pictures even the sheep dog as saying to the sheep: "For I am the one that saves you also so that you are neither stolen by men nor seized by wolves." Hippocrates has psuchn kateqeto (he laid down his life, i.e. died). In Judges 12:3eqhka thn psuchn means "I risked my life." The true physician does this for his patient as the shepherd for his sheep. The use of uper here (over, in behalf of, instead of), but in the papyri uper is the usual preposition for substitution rather than anti. This shepherd gives his life for the sin of the world ( Judges 1:29 ; 1 John 2:2 ).