mysterion

Mysterion is a word with roots in the Greek term μυστήριον (mystḗrion), meaning "a mystery" or "secret." In classical and biblical Greek, it referred to hidden truths or things revealed by God. In the New Testament, the term describes divine truths that were previously hidden but are now disclosed in Christ, such as the mystery of God or the mystery of Christ (for example, Romans 16:25–27 and Ephesians 3:3–6). English translations typically render μυστήριον as "mystery," often with the sense of a divinely revealed secret.

In Christian theology, mysterion conveys the idea that God’s salvific plan transcends human knowledge and is made known through revelation. The term also extends to liturgical and sacramental language in various Christian traditions, where sacraments are called mysteries or "holy mysteries," reflecting the belief that certain divine realities are made present through rites while remaining ultimately beyond full human comprehension. In Orthodox and some Catholic contexts, mysteries can denote both doctrinal truths and the rites through which grace is imparted.

In popular culture, Mysterion is the masked superhero identity of Kenny McCormick in the animated series South Park. Debuting in the show’s later seasons as a recurring alter ego, Mysterion appears as Kenny’s vigilante persona, complete with cape and mask, and serves as a recurring motif within the show’s satire of superhero tropes.

The term’s usage across religious, linguistic, and cultural contexts highlights a common theme: a hidden or transcendent reality revealed in and through human experience, belief, and storytelling.