How do we know the doctrine of unity in the church is true?

The truth of the church's unity is firmly established in Scripture, particularly through Ephesians 4:3-4, where Paul urges believers to endeavor to maintain the unity of the Spirit in the bond of peace. This passage underscores that there is one body and one Spirit, calling believers to recognize that their collective identity in Christ transcends individual differences. This unity is not contingent upon external forms or human-designed structures but is inherently linked to the work of the Holy Spirit.

Further supported by the teaching that all believers are baptized by one Spirit into one body, this doctrine affirms that true unity is a spiritual reality for those who are in Christ. The existence of divisions and disagreements among believers highlights the need for continual growth in spiritual maturity and proximity to Christ, who is the source of our unity. Ultimately, the belief in this unity is deeply rooted in the sovereign grace of God, who calls and sustains His people in their shared faith and love for one another.