Problem: Paul writes, “No one can say, ‘Jesus is Lord,’ except by the Holy Spirit” (1 Cor. 12:3). However, false teachers will often claim to speak for God, using the phrase “Jesus is Lord.” For instance, consider the documentary Marjoe. In this film, a non-Christian swindler steals thousands of dollars from Christian people, claiming to speak for God. In addition to modern examples, even within the NT, we see non-Christians speaking God’s truth (Acts 16:16-17; c.f. Mt. 7:21; Jas. 2:19). How does this all square with this passage?
Solution: In 1 Corinthians 12:3, Paul is simply trying to instruct the Corinthians to discern true religion from false religion. The context is idolatry (v.2). In this context, Paul instructs them to discern the true God from false gods. We do not discern a false teacher based on how they teach (1 Cor. 2:1-4) or based on how they look (1 Cor. 4:8; 2 Cor. 11:14). Instead, Paul argues that we should judge false teaching based on what is taught. In other words, doctrine is important (1 Cor. 14:29).
However, doctrine isn’t the only test to discern a false teacher; it is simply one test. The rest of the NT gives more information on this subject. To spot a false teacher, we also need to look to their lifestyle and their deeds. Paul elsewhere speaks of identifying false teachers who “by their deeds they deny Him” (Titus 1:16). James writes, “Who among you is wise and understanding? Let him show by his good behavior his deeds” (Jas. 3:13). When questioning the leadership of Diotrephes, John wrote, “If I come, I will call attention to his deeds which he does” (3 Jn. 10). Therefore, to spot a false teacher, we need to consider both doctrine and deeds.
“Wherefore I give you to understand, that no man speaking by the Spirit of God calleth Jesus accursed: and that no man can say that Jesus is the Lord, but by the Holy Ghost. (1 Cor 12:3)”
