1 Corinthians 12: 3
No one can say, “Jesus is Lord,” except by the Holy Spirit. The word for Lord is kyrios, the word commonly used in the Greek version of the Old Testament for Jehovah. To say that Jesus is the Lord, therefore, in the apostle’s sense is to acknowledge him to be truly God. And as the word Jesus here, as before, designates the historical person known by that name, who was born of the Virgin Mary, saying that Jesus is Lord is to acknowledge that that person is God revealed in the flesh. In other words, the confession includes the acknowledgment that he is truly God and truly man. What the apostle says is that no one can make this acknowledgment except by the Holy Spirit. This, of course, does not mean that no one can utter these words unless he is under special divine influence; it means that no one can truly believe and openly confess that Jesus is God revealed in the flesh unless he is enlightened by the Spirit of God.
This is precisely what our Lord himself said when Peter confessed him to be the Son of God. “Blessed are you, Simon son of Jonah, for this was not revealed to you by man, but by my Father in heaven” (Matthew 16:17). The same thing is also said by the apostle John: “This is how you can recognize the Spirit of God: Every spirit that acknowledges that Jesus Christ has come in the flesh is from God, but every spirit that does not acknowledge Jesus is not from God” (1 John 4:2–3). And, “if anyone acknowledges that Jesus is the Son of God, God lives in him and he in God” (1 John 4:15).
Hodge, C. (1995). 1 Corinthians (pp. 216–217). Wheaton, IL: Crossway Books.