How do we know the priesthood of all believers is true?

The doctrine of the priesthood of all believers is rooted in Scriptures like 1 Peter 2:9, which proclaims that all believers constitute a 'royal priesthood.' This signifies that through faith in Christ, individuals are not merely subjects of spiritual authority but are themselves called to serve God in worship and ministry. Unlike the Old Testament, where the priesthood was confined to the tribe of Levi, the New Covenant establishes that Christ, our High Priest after the order of Melchizedek, allows all believers to approach God boldly. This emphasizes the involvement of every Christian in worship, reflecting their status as priests who are called to offer spiritual sacrifices, prayers, and praises. Furthermore, Revelation 1:6 supports this notion by declaring that Christ has made us kings and priests unto God. Thus, every believer participates in the mission of proclaiming God's glory and leading others in worship, demonstrating the expansive nature of the gospel.