Exodus 22:20

The person who sacrifices to any god except Jehovah must be condemned and destroyed.

Deuteronomy 17:2-5

In one of the cities Jehovah your God is giving you, there may be a man or woman among you who is doing what Jehovah considers evil. This person may be disregarding the conditions of Jehovah's covenant.

Numbers 25:7-8

Phinehas, son of Eleazar and grandson of the priest Aaron, saw this. He left the assembly and grabbed a spear in his hand.

Deuteronomy 13:1-15

If a prophet or an interpreter of dreams appears among you and gives you a sign or a wonder (portent) (omen) (forecast of the future),

Deuteronomy 18:20

Any prophet who dares to say something in my name that I did not command him to say or who speaks in the name of other gods must die.

Numbers 21:3

Jehovah heard them and helped them conquer the Canaanites. The Israelites completely destroyed them and their cities, and named the place Hormah.

Numbers 25:2-4

The Moabites invited the people to the sacrifices of their gods. The people ate and bowed down to their gods.

Joshua 23:15-16

Just as he kept every promise that he made to you, so he will carry out every threat.

Treasury of Scripture Knowledge

Summary

He that sacrificeth unto any god, save unto the LORD only, he shall be utterly destroyed.

Bible References

Sacrificeth

Numbers 25:2
The Moabites invited the people to the sacrifices of their gods. The people ate and bowed down to their gods.
Deuteronomy 13:1
If a prophet or an interpreter of dreams appears among you and gives you a sign or a wonder (portent) (omen) (forecast of the future),
Deuteronomy 17:2
In one of the cities Jehovah your God is giving you, there may be a man or woman among you who is doing what Jehovah considers evil. This person may be disregarding the conditions of Jehovah's covenant.
Deuteronomy 18:20
Any prophet who dares to say something in my name that I did not command him to say or who speaks in the name of other gods must die.

Utterly

Numbers 21:3
Jehovah heard them and helped them conquer the Canaanites. The Israelites completely destroyed them and their cities, and named the place Hormah.
Joshua 23:15
Just as he kept every promise that he made to you, so he will carry out every threat.