Many people, when they die, will stand before Jesus and say:
Lord, Lord, did we not prophesy in Your name, and in Your name cast out demons, and in Your name perform many miracles? - Matthew 7:22
And Jesus will say to them:
I never knew you; depart from Me, you who practice lawlessness. - Matthew 7:23
Get your Bible out and read Matthew 7:21-23. These are some of the most frightening verses in the Bible.
They describe people who believe with all their heart that they are saved. They have no doubt that they know Jesus and they've done many great things that prove this is true. Put Jesus says, 'Depart from me...' He doesn't know them.
Are you truly trusting Jesus? Scripture says to examine yourself to see if you are in the faith (2 Corinthians 13:5). Have you done that?
Do you read your Bible regularly? Do you fear false teaching? Are you growing in your obedience to God? Are you growing in your understanding of what God wants? Do you regularly share the good news about Jesus with others?