1 Corinthians 8:4

Now concerning [the matter of] eating foods [once] offered as sacrifices to idols, we know that an idol is [really] nothing in the world [at all], and that there is only one God.

1 Corinthians 10:19-20

So, what am I saying? That an animal sacrificed to idols is [really] anything, or that an idol [itself] is anything?

1 Timothy 4:1

Now the Holy Spirit specifically says that in later times [Note: "Later times" in the New Testament usually refers to the period following the first coming of Christ and the establishment of the church], some people will fall away from the faith [i.e., the true teaching of Christianity]. They will pay attention to deceitful spirits [i.e., lying people] and the teaching of evil spirits.

Revelation 9:20

And the rest of mankind, who were not killed by these plagues, [still] did not repent of what they had made with their hands [i.e., their idolatry]. They did not stop worshiping demons, and gold, silver, brass, stone and wooden idols, which can neither see, nor hear nor walk.

Treasury of Scripture Knowledge

Summary

They sacrificed unto devils, not to God; to gods whom they knew not, to new gods that came newly up, whom your fathers feared not.

Bible References

Sacrificed

1 Corinthians 10:20
[Certainly not!] But I am saying that the Gentile sacrifices are [really] offered to evil spirits and not to God. And I do not want you to have fellowship with evil spirits.
1 Timothy 4:1
Now the Holy Spirit specifically says that in later times [Note: "Later times" in the New Testament usually refers to the period following the first coming of Christ and the establishment of the church], some people will fall away from the faith [i.e., the true teaching of Christianity]. They will pay attention to deceitful spirits [i.e., lying people] and the teaching of evil spirits.
Revelation 9:20
And the rest of mankind, who were not killed by these plagues, [still] did not repent of what they had made with their hands [i.e., their idolatry]. They did not stop worshiping demons, and gold, silver, brass, stone and wooden idols, which can neither see, nor hear nor walk.

Not to god

1 Corinthians 8:4
Now concerning [the matter of] eating foods [once] offered as sacrifices to idols, we know that an idol is [really] nothing in the world [at all], and that there is only one God.
1 Corinthians 10:19
So, what am I saying? That an animal sacrificed to idols is [really] anything, or that an idol [itself] is anything?