How did Theodosius I’s penance affect later ideas about church power and imperial power?

The penance performed by Theodosius I in 390, following his order for a brutal massacre in Thessalonica, is often misinterpreted. While some later historical narratives have claimed this event established the supremacy of the church over temporal power, this interpretation is a myth generated long after the fact.1

In reality, the emperor’s compliance with Bishop Ambrose’s demand for public penance was not a surrender of imperial authority. Instead, it functioned as a demonstration of the power of atonement over a penitent sinner. Theodosius remained committed to preserving the emperor’s authority throughout his reign, even while maintaining a friendly relationship with the church. He consistently took care to ensure that the material interests of the state were not sacrificed to the clergy and resisted granting bishops undue influence in government affairs. Consequently, the idea that this act fundamentally shifted the balance of power to the church is a later construction rather than a reflection of the political reality of the time.1