What is the significance of Christ being the cornerstone of the church?

In Ephesians 2:20, Christ is identified as the chief cornerstone of the church, signifying His foundational role in salvation and the unity of believers. The cornerstone is crucial, as it provides stability and alignment for the entire structure; similarly, Christ's righteousness and sacrifice support the faith and unity of the church. As believers are built upon this cornerstone, they are spiritually united, with their identity and acceptance before God fully resting in Him. This metaphor reinforces that the church's integrity and purpose are derived from Christ alone, ensuring that each believer, regardless of background, has equal standing before God.