We know Jesus died for our sins because Scripture assures us that He suffered once for all, the just for the unjust, to bring us to God (1 Peter 3:18).
The assurance of Christ's atoning work for our sins is grounded in the biblical truth that He, the just One, died for the unjust. This is stated clearly in 1 Peter 3:18, which articulates that His suffering was a necessary means to reconcile us to God. This truth is further supported by the affirmation of grace through faith, where believers come to understand and accept this gift. When God enables a person to believe in Christ, it catalyzes the assurance that He died for them specifically, highlighting God's sovereignty in salvation, where He preordained before the foundation of the world those whom He would save.
Scripture References:
1 Peter 3:18, Romans 6:23, Ephesians 1:4-5, 1 Corinthians 15:3, Isaiah 53, Romans 8:34, Acts 2:23, Galatians 3:13, Romans 8:1, Romans 5:8, Matthew 1:21, John 10:15
Commentary