How do you know if someone is a true “believer”?

QUESTION

How do we know who is a real “believer” and who is not?

ANSWER

Anyone can claim to be in in Christ (a born-again Christian), but the Bible tells us that only those with the Spirit of God are truly of Christ. For example, in the book of Acts chapter 8 we learn of a man who desired to be associated with Christinas and Christianity, but he didn’t possess the Spirit “by faith” and therefore was deemed to be an unbeliever.

Acts 8:18 Now when Simon saw that the Spirit was bestowed through the laying on of the apostles’ hands, he offered them money, 
Acts 8:19 saying, “Give this authority to me as well, so that everyone on whom I lay my hands may receive the Holy Spirit.” 
Acts 8:20 But Peter said to him, “May your silver perish with you, because you thought you could obtain the gift of God with money! 
Acts 8:21 “You have no part or portion in this matter, for your heart is not right before God. 
Acts 8:22 “Therefore repent of this wickedness of yours, and pray the Lord that, if possible, the intention of your heart may be forgiven you. 
Acts 8:23 “For I see that you are in the gall of bitterness and in the bondage of iniquity.” 

It should not surprise us that men claim to have the Spirit when they do not. The unbelieving world cannot understand what they do not have, so from their limited perspective (like Simon), they can only assume that it’s through an association or relationship with other people, when in reality it is only a relationship with the Living God through His Son, Jesus Christ.

So how do we know if someone is a really a Christian? Our ability has to discern true faith in another individual has always been limited and subject to error since true faith is a spiritual (invisible) relationship. Even so, scripture does give us a clue as to what to look for as a by product of true faith in a man or woman’s life. Scripture calls it “spiritual fruit”:

Matt. 7:15  “Beware of the false prophets, who come to you in sheep’s clothing, but inwardly are ravenous wolves.
Matt. 7:16 “You will know them by their fruits. Grapes are not gathered from thorn bushes nor figs from thistles, are they?
Matt. 7:17 “So every good tree bears good fruit, but the bad tree bears bad fruit.
Matt. 7:18 “A good tree cannot produce bad fruit, nor can a bad tree produce good fruit.
Matt. 7:19 “Every tree that does not bear good fruit is cut down and thrown into the fire.
Matt. 7:20 “So then, you will know them by their fruits.
Matt. 7:21  “Not everyone who says to Me, ‘Lord, Lord,’ will enter the kingdom of heaven, but he who does the will of My Father who is in heaven will enter.

Jesus himself tells us that we will know the difference by seeing different “fruit”. This fruit that He speaks of is spiritual fruit. Pauls also tells us that the spiritual fruit of a believer will be easily recognizable and be in stark contrast to the fruit of an unbeliever:

Gal. 5:19 Now the deeds of the flesh are evident, which are: immorality, impurity, sensuality, 
Gal. 5:20 idolatry, sorcery, enmities, strife, jealousy, outbursts of anger, disputes, dissensions, factions, 
Gal. 5:21 envying, drunkenness, carousing, and things like these, of which I forewarn you, just as I have forewarned you, that those who practice such things will not inherit the kingdom of God. 
Gal. 5:22 But the fruit of the Spirit is love, joy, peace, patience, kindness, goodness, faithfulness, 
Gal. 5:23 gentleness, self-control; against such things there is no law. 
Gal. 5:24 Now those who belong to Christ Jesus have crucified the flesh with its passions and desires. 
Gal. 5:25 If we live by the Spirit, let us also walk by the Spirit. 

As you see spiritual changes in a believers life and their “fruit” begin to change you can have confidence in their testimony of faith in Jesus Christ. However… this leads to warning: Be careful that you do not become a “fruit inspector”. Our inability to be true in our discernment and lack of 100% accuracy should cause us to refrain from having our spiritual magnifying glass out every time we are at Church in most cases. True validation of someone’s faith should only be sought when someone is seeking leadership or teaching positions in the Church.

For more about this topic, I encourage you to read the book of Galatians.