What does the Bible say about spiritual oneness among believers?

In John 17:21, Jesus prayed for the unity of His followers, expressing a profound spiritual oneness that mirrors the relationship between the Father and the Son. This oneness is not about superficial agreements among differing denominations, but a deep, spiritual connection that is established by God alone. Ephesians 2:14-16 emphasizes that Christ has broken down the barriers that separate believers, creating one body in Him through the cross, thus achieving peace and unity. This divine work ensures that all true believers, regardless of background, are unified in their faith and identity in Christ.