How Do We Know If Someone Is Truly a Christian?

The only real way for us, as humans, to know if someone has truly become a Christian is to observe that person’s life on the outside. Since we cannot see the interior of the human heart as God does, we have to look for some result or indicator of their faith.

“Show me your faith without deeds, and I will show you my faith by what I do. You believe that there is one God. Good! Even the demons believe that and shudder. You foolish man, do you want evidence that faith without deeds is useless?” (James 2:18-20 NIV).

Jesus said, “Therefore by their fruits you will know them. Not everyone who says to Me, ‘Lord, Lord,’ shall enter the kingdom of Heaven, but he who does the will of My Father in Heaven” (Matthew 7:20–21).

If a person does not show any fruit—that is, any visible evidence of the change that has taken place in his heart since receiving Jesus Christ as his personal Savior—then that individual is not a Christian. Time will tell if a person who comes forward at a crusade or church invitation to make a profession of faith has actually gone through a conversion.

Deeds or works don’t save a person, but they are good evidence that the person is saved.