What is the significance of being 'in Christ' for believers?

The phrase 'in Christ' is significant for believers as it encapsulates our spiritual union with Jesus, resulting in several profound theological implications. As Paul notes in Philippians 3:9, being found in Him means we are identified with His righteousness, which is not based on our works but through faith. This union signifies that we share in Christ’s death, resurrection, and the new life that comes from Him (Galatians 2:20). It is through this relationship that believers are reassured of their eternal standing before God, for we are made righteous by God's grace in Christ, ensuring that our salvation is secure and unfaltering.