1 Corinthians 8:4

As to the eating therefore of things sacrificed to idols, we know that an idol is nothing in the world, and that there is no other God but one.

1 Corinthians 10:19-20

What say I then? that the idol is any thing, or that what is sacrificed to an idol is in itself any thing to stumble at?

1 Timothy 4:1

Now the Spirit expressly saith, that in latter times some shall apostatize from the faith, attending to seducing spirits,

Revelation 9:20

And the rest of the men, who were not killed by these plagues, yet repented not of the works of their hands, so as not to worship demons, and idols of gold, and of silver, and of brass, and of stone, and of wood; 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
No: but this I say, that what the Gentiles sacrifice, they sacrifice to demons, and not to God.
1 Timothy 4:1
Now the Spirit expressly saith, that in latter times some shall apostatize from the faith, attending to seducing spirits,
Revelation 9:20
And the rest of the men, who were not killed by these plagues, yet repented not of the works of their hands, so as not to worship demons, and idols of gold, and of silver, and of brass, and of stone, and of wood; which can neither see, nor hear, nor walk:

Not to god

1 Corinthians 8:4
As to the eating therefore of things sacrificed to idols, we know that an idol is nothing in the world, and that there is no other God but one.
1 Corinthians 10:19
What say I then? that the idol is any thing, or that what is sacrificed to an idol is in itself any thing to stumble at?