The doctrine of reconciliation is stated as such in 2 Corinthians 5:18, Ephesians 2:16, and Colossians 1:20-21. It means we have “peace” with God through our Savior Jesus Christ. “Peace” and “reconciliation” are synonymous terms in Ephesians 2:14,15,17; 4:3; 6:15.
The actual work of reconciliation was completed on the cross. We become reconciled the split second we believe in Christ. The believer is guaranteed a heavenly citizenship based on reconciliation.
Positionally, every believer is a citizen of heaven: Luke 20:10; Ephesians 2:14-19; Philippians 3:20.