How do we know that justification is eternal?

In 2 Timothy 1:9, we learn that our salvation and calling are not based on our works but on God's purpose and grace given to us in Christ Jesus before the world began. This indicates that justification is not a response to our actions but a divine decree, secured by Christ’s sacrifice. As such, justification is eternal because it originates from God's unchanging will and is unaffected by human actions. Once justified, a believer’s standing before God is secure, as God does not reverse His declarations. Understanding this eternal aspect of justification brings assurance and comfort to believers, affirming that their salvation is entirely the work of God's sovereign grace.