"Do you not know that the unrighteous will not inherit the kingdom of God? Do not be deceived. Neither fornicators, nor idolaters…" (1 Corinthians 6:9). Idolaters are those who worship false gods, who give themselves over to idols, who take part in idol worship. This was obviously a big problem in Corinth with all of its temples to pagan deities. "I wrote to you in my epistle not to keep company with sexually immoral people. Yet I certainly did not mean with the sexually immoral people of this world, or with the covetous, or extortioners, or idolaters, since then you would need to go out of the world. But now I have written to you not to keep company with anyone named a brother, who is sexually immoral, or covetous, or an idolater, or a reviler, or a drunkard, or an extortioner-not even to eat with such a person" (1 Corinthians 5:9-11). Paul here recognized that there were idolatrous people of this world and even that a brother could become an idolater, thus needing to be disciplined.
Idolatry was always a special problem among the people of Israel. When God gave them the Ten Commandments, we read, "And God spoke all these words, saying: 'I am the Lord your God, who brought you out of the land of Egypt, out of the house of bondage. You shall have no other gods before Me. You shall not make for yourself a carved image-any likeness of anything that is in heaven above, or that is in the earth beneath, or that is in the water under the earth'" (Exodus 20:1-4). A prohibition against idolatry was the very first of the Ten Commandments given, and it was the very first one broken as the Israelites built the golden calf. God sent prophets like Isaiah to warn His people against idolatry and explained that their serving idols was the main reason why He sent them into captivity.
Idolatry was also a problem in the early church, especially for those Christians who had come out of a heathen environment. We have already seen how it affected the Corinthians. "Therefore concerning the eating of things offered to idols, we know that an idol is nothing in the world, and that there is no other God but one. For even if there are so-called gods, whether in heaven or on earth (as there are many gods and many lords), yet for us there is one God, the Father, of whom are all things, and we for Him; and one Lord Jesus Christ, through whom are all things, and through whom we live. However, there is not in everyone that knowledge; for some, with consciousness of the idol, until now eat it as a thing offered to an idol; and their conscience, being weak, is defiled. But food does not commend us to God; for neither if we eat are we the better, nor if we do not eat are we the worse. But beware lest somehow this liberty of yours become a stumbling block to those who are weak. For if anyone sees you who have knowledge eating in an idol's temple, will not the conscience of him who is weak be emboldened to eat those things offered to idols?" (1 Corinthians 8:4-10). The apostle John ended his first epistle with the warning, "Little children, keep yourselves from idols. Amen" (1 John 5:21).
While there are places on earth even now where literal idolatry is still common, we do not have much of a problem with idols of stone, wood, or metal in our culture today. However, we do have problems with idols of the heart. "Now some of the elders of Israel came to me and sat before me. And the word of the Lord came to me, saying, 'Son of man, these men have set up their idols in their hearts, and put before them that which causes them to stumble into iniquity. Should I let Myself be inquired of at all by them? Therefore speak to them, and say to them, "Thus says the Lord God: 'Everyone of the house of Israel who sets up his idols in his heart, and puts before him what causes him to stumble into iniquity, and then comes to the prophet, I the Lord will answer him who comes, according to the multitude of his idols'"'" (Ezekiel 14:1-4). One common idol of the heart in our materialistic society is money, material gain, physical wealth, temporal good.
"For this you know, that no fornicator, unclean person, nor covetous man, who is an idolater, has any inheritance in the kingdom of Christ and God" (Ephesians 5:5. "Therefore put to death your members which are on the earth: fornication, uncleanness, passion, evil desire, and covetousness, which is idolatry" (Colossians 3:5). Why is it so important not to make money or riches an idol? "But those who desire to be rich fall into temptation and a snare, and into many foolish and harmful lusts which drown men in destruction and perdition. For the love of money is a root of all kinds of evil, for which some have strayed from the faith in their greediness, and pierced themselves through with many sorrows" (1 Timothy 6:9-10). We must put to death all forms of idolatry, including covetousness, because those who are guilty of it "will not inherit the kingdom of God."