How do we know that Christians are all sinners saved by grace?

In Romans 3:23, the Apostle Paul declares, 'for all have sinned and fall short of the glory of God,' which establishes a universal condition of humanity: every person, including Christians, is a sinner in need of God's grace. This fundamental truth underscores the Reformed understanding of salvation, where no one can claim righteousness on their own. Instead, we rely on the grace of God through faith in Jesus Christ, who redeems us despite our sinful state. Historically, the Reformed tradition emphasizes that our identity as 'sinners saved by grace' calls us to humility and recognition of the common struggle we share in our flesh.