In 2.Cor 13:5, we read, “5 Examine yourselves to see whether you are in the faith; test yourselves. Do you not realize that Christ Jesus is in you—unless, of course, you fail the test?”
Are you saved?
In John 10:28, Jesus says if we are saved, no one can take our salvation from us. Did you notice what John 10:28 did not say? We read how nobody can take our salvation from us, but we can still do something that causes us to lose our salvation.
This is why Paul says, in 2.Cor 13:5; we are to examine ourselves to see if we are still saved. How do we examine ourselves to see if we are still saved? In 1.John 2:6, the Bible says if we claim to be in Christ, we have to live our lives as He did. If we do not live as He lived His life, our faith in the cross is dead and unable to save us. (James 2). So the test Paul is referring to in 2.Cor 13:5 is to see if we imitate the life of Christ.
How did Christ live His life?
As a Christian, you already know the answer, He was sinless and perfect because He kept the law of Moses. If the Bible says we are to live as He lived, and He kept the law of Moses, then we have to keep the law to remain saved.
Are you saved?
Most Christians believe the lie that says the law of Moses was done away with at the cross. If you believe this lie, you will one day hear “depart from Me for I never knew you, you who rejected the law” (Matt 7:21-23)
Repent from this lie and return to the law so your faith in the cross can save you.