Which term describes the act of paying debts to save sinners from slavery to sin?

The term that best describes the act of paying debts to save sinners from slavery to sin is redemption. This concept is rooted in Christian theology, where it signifies the deliverance from sin and its consequences through the payment of a ransom. In the context of salvation, redemption implies that Jesus' sacrifice atones for humanity's sins, freeing believers from the bondage of sin and enabling them to have a restored relationship with God.

The other terms, while relevant in theological discussions, do not specifically capture this idea of paying a debt. Expiation refers to the act of making amends or atoning for wrongdoing, focusing more on the removal of guilt rather than the payment of a ransom. Propitiation involves appeasing or satisfying a deity's wrath, aligning more with turning away God's displeasure rather than the act of liberating sinners from sin itself. Reconciliation denotes the process of restoring a relationship that has been estranged, which is a subsequent step that occurs as a result of redemption. Thus, redemption is the most accurate term for the act of paying debts to free sinners.