declaration_of_repentance_interaction_effect

declaration_of_repentance_interaction_effect = {
	if = {
		limit = { scope:declaration_hook = yes }
		scope:puppet_or_actor = {
			use_hook = scope:recipient
		}
	}

	scope:puppet_or_actor = {
		if = {
			limit = {
				scope:declaration_hook = no
				NOT = { rite ?= { rite_has_parameter = tenet_purgatory_absolution_costs_less_prestige } }
			}
			#Lose a ton of prestige (e.g., Henry's Walk to Canossa)
			add_prestige = massive_prestige_loss
			add_prestige_level = -1
		}
		else_if = {
			limit = {
				scope:declaration_hook = no
			}
			add_prestige = major_prestige_loss
		}

		#Character cannot be excommunicated again for 10 years.
		remove_trait = excommunicated
		clear_excommunication_tracking_effect = yes
		add_character_modifier = {
			modifier = excommunication_recently_lifted
			years = 10
		}

		stress_and_fulfillment_impact = {
			cynical = minor_stress_impact_gain
		}
	}
	scope:recipient = {
		add_prestige = major_prestige_gain
		add_opinion = {
			modifier = repentant_opinion
			target = scope:puppet_or_actor
			opinion = 10
		}
	}
	scope:puppet_or_actor = {
		if = {
			limit = {
				any_character_situation = {
					situation_type = the_christian_church
				}
				situation:the_christian_church ?= {
					situation_top_has_catalyst = catalyst_declaration_of_repentance
				}
			}
			if = {
				limit = {
					highest_held_title_tier >= tier_kingdom
				}
				situation:the_christian_church = { trigger_situation_catalyst = catalyst_declaration_of_repentance }
			}
			else = {
				situation:the_christian_church = { trigger_situation_catalyst = catalyst_declaration_of_repentance_minor }
			}
		}
	}
}

As written in game/common/scripted_effects/00_interaction_effects.txt.