James 2:18 (NLT)

Now someone may argue, “Some people have faith; others have good deeds.” But I say, “How can you show me your faith if you don’t have good deeds? I will show you my faith by my good deeds.”

Lots of people “believe in God.” Lots of people say they “have faith.” Lots of people are wrong. James continues his teaching on the evidence of true, saving faith: good works.

The word “show” means to exhibit or demonstrate and it is inseparable from true, saving faith. We know a person has genuine faith by what their life produces, which begs the question: what does genuine faith produce? Jesus said it produces obedience to His commands (John 14:15). Paul gives us a list in Galatians 5 called the Fruit of the Spirit: love, joy, peace, patience, kindness, goodness, faithfulness, gentleness, and self-control. In Micah 6:8 we are told that God wants us to act justly, love mercy, and walk humbly with Him. There is no lack of biblical input by which we all must test our profession of faith.

Ultimately, it’s not for any of us to say as to whether somebody else is “really a Christian” or not. I can’t tell you what’s truly inside your heart, but God certainly can. James is warning anyone who claims to have faith that there had better be a testimony of good works to go along with that profession; otherwise, that workless faith is dead.