Question: What does I H S mean? What specifically do these letters stand for?
Bonus question: Who is responsible for bringing “ I H S” into the center of Catholic devotional life?
Answer: I H S is a Christogram or an abbreviation (in Greek) of Jesus' name. The Christogram is a contraction derived from the Greek word ΙΗΣΟΥΣ, Jesus. I (iota), H (eta), Σ or S (sigma).
Bonus Answer: St. Bernardine of Siena
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