[expand]
Thermal spring use continued through religious changes because it was medically effective and practically valuable. Christianity had no objection to bathing, and therapeutic benefits were obvious to everyone. The practices adapted—old rituals might be replaced with Christian prayers, but the springs themselves remained community resources, valued and used.
Modern medical research confirms many traditional uses. Heat therapy reduces inflammation, improves circulation, eases pain. Sulfur has antibacterial and antifungal properties. Mineral absorption through skin occurs and can be therapeutic. The old knowledge was empirically accurate, refined through generations of observation and use.
[/expand]