How do we know that Jesus Christ is a propitiation for our sins?

In 1 John 2:2, it is clearly stated that Jesus Christ is the propitiation for our sins. The term 'propitiation' refers to His role as a sin-bearing sacrifice that satisfies the justice of God. This means that through His death, He appeased God's wrath against sin, ensuring that believers would not face His judgment. The concept of propitiation is supported by passages like Romans 3:25, where God set forth Christ as a propitiation through faith in His blood. This is a foundational truth in Reformed theology—Christ did not just die for a potential salvation but achieved real, effective reconciliation for those who are elect. Thus, He is the surety of salvation for all for whom He died.