We just learned about the Christian symbol Chi Rho.
Another Christian symbol is the Iota Eta, also called the IH Monogram.
In Greek, Jesus is spelled ἸΗΣΟῦΣ.
Ἰ - Iota
Η - Eta
Σ - Sigma
Ο - Omicron
ῦ - Upsilon
Σ - Sigma
Iota is like an I, and Eta is like an H.
Sometimes people would combine the ἸΗ into one symbol to mean Jesus.
(from: wikipedia - christian symbolism)
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