Iota is the first letter of Iesous (Ιησους), Greek for Jesus . Chi is the first letter of Christos (Χριστóς), Greek for " anointed ". Theta is the first letter of Theou (Θεοῦ), genitive case of Θεóς "God". Upsilon is the first letter of Huios (Υἱός), Greek for Son. Sigma is