The following blog post was originally published in February, 2020. —ed.

There is only one true God, and He demands exclusive worship. That is the essence of the first commandment God gave to Moses on Mount Sinai. It is also the unshakable and unchanging truth about God from eternity past to eternity future.

Deuteronomy 6:4–5 points to the oneness and exclusivity of God as the essence of His law: “Hear, O Israel! The Lord is our God, the Lord is one! You shall love the Lord your God with all your heart and with all your soul and with all your might.” The truth that there is one God was fundamental to the Hebrew identity and distinctive of the Israelite nation. The Israelites, living in the midst of dozens of polytheistic cultures, were saying, “There is only one God.” Although they had initially become a nation while living among the Egyptians (whose proliferation of false gods was carried to preposterous extremes) they had held to their faith in Yahweh as the one true God. God had revealed Himself to them as one God, and any Israelite who dared to worship another god was put to death.

Jesus affirmed the importance of God’s singularity. In Mark 12, a scribe asked Him what was the greatest of the commandments and Christ, without hesitation, echoed Deuteronomy 6:4–5, “The foremost is, ‘Hear, O Israel! The Lord our God is one Lord; and you shall love the Lord your God with all your heart, and with all your soul, and with all your mind, and with all your strength’” (Mark 12:29–30). Without denying His own deity, and yet at the same time acknowledging that there is only one God, Jesus taught that the greatest commandment is to give total allegiance with all your heart, soul, mind, and strength to the one true God.

The Father and the Son Are One

In John 10:30, Jesus said, “I and the Father are one.” That is a claim of absolute equality with God; yet at the same time it is a reaffirmation that there is but one God.

Paul emphasized the unity and equality of the Father and the Son in his first epistle to the Corinthians. The Corinthians were living in a typically pagan polytheistic society. Idols were everywhere in the city, and those who worshiped them would bring offerings of food. The priests of the idols’ temples operated food markets, where they sold the uneaten food that had been offered to the idols. Some believers were buying that food, perhaps because they could get it for a much better price than the food at commercial markets.

Christians who had been saved out of pagan worship were troubled over those who were eating food that had been offered to idols. They would go over for dinner and then refuse to eat if they found out the food had come from idol offerings. It was causing serious problems in their fellowship, and Paul wrote 1 Corinthians 8 to resolve the issue. Verse 4 sums up his teaching: “Therefore concerning the eating of things sacrificed to idols, we know that there is no such thing as an idol in the world, and that there is no God but one” (1 Corinthians 8:4) An idol isn’t anything. If food offered to idols is the best bargain in town, get it. Eat it. It isn’t going to make a bit of difference, spiritually. An idol is nothing. And there is no other God but one.

Paul continues,

For even if there are so–called gods whether in heaven or on earth, as indeed there are many gods and many lords, yet for us there is but one God, the Father, from whom are all things and we exist for Him; and one Lord, Jesus Christ, by whom are all things, and we exist through Him. (1 Corinthians 8:5–6)

How can all things be by God the Father and all things be by the Lord Jesus, and we exist through God and we exist through the Lord Jesus? At the surface, it might seem like a contradiction, but clearly, Paul is teaching that God the Father and the Lord Jesus Christ are one. It is another claim to the absolute deity of Jesus Christ without dividing God into parts.

The Father and the Spirit Are One

The Holy Spirit also is specifically called God. Peter said, “Ananias, why has Satan filled your heart to lie to the Holy Spirit and to keep back some of the price of the land?” (Acts 5:3). Then in the next verse, he spells it out: “You have not lied to men but to God.” (Acts 5:4). If lying to the Holy Spirit constitutes lying to God, it necessarily follows that the Holy Spirit is, in fact, God.

First Corinthians 3:16 says, “Do you not know that you are a temple of God?” And as proof, it adds, “the Spirit of God dwells in you.” In chapter 6 the argument is carried further. Verse 19 says, “Your body is a temple of the Holy Spirit who is in you” (1 Corinthians 6:19). And verse 20 adds the exhortation, “therefore glorify God in your body” (1 Corinthians 6:20). That equates the Holy Spirit with God. Along with dozens of other verses, indeed the entire teaching of the New Testament, it underscores this truth: The Holy Spirit is God.

So how can we reconcile the fact that Scripture teaches that the Father is God, Jesus is God, and the Holy Spirit is God, and yet there is but one God? I’ll answer that next time as we consider the doctrine of the Trinity.

(Adapted from Worship)