Judges 2:3

And I also said, I will not drive them out from before you, but they shall be thorns in your sides, and their gods shall be a snare to you.

Numbers 33:55

But if you will not drive out the people of the land from before you, then it will be, those of them whom you let remain shall be goads in your eyes and thorns in your sides, and they shall trouble you in the land in which you live.

Joshua 23:13

know for a certainty that Jehovah your God will no more drive out these nations from before you. But they shall be snares and traps to you, and whips in your sides, and thorns in your eyes, until you perish from off this good land which Jehovah your God has given you.

Deuteronomy 7:16

And you shall destroy all the people which Jehovah your God shall deliver you. Your eye shall have no pity upon them, neither shall you serve their gods, for they will be a snare to you.

Judges 2:21

I also from now on will not expel any from before them of the nations that Joshua left when he died;

Judges 3:6

And they took their daughters to be their wives, and gave their daughters to their sons, and served their gods.

Psalm 106:36

And they served their idols, which were a snare to them.

Exodus 23:33

They shall not dwell in your land lest they make you sin against Me. For if you serve their gods, it surely will be a snare to you.

Exodus 34:12

Take heed to yourself, lest you make a covenant with the people of the land where you go, lest it be for a snare in the midst of you.

1 Kings 11:1-7

And King Solomon loved many foreign women, even the daughter of Pharaoh, Moabites, Ammonites, Edomites, Sidonians, Hittites;

Treasury of Scripture Knowledge

Summary

Wherefore I also said, I will not drive them out from before you; but they shall be as thorns in your sides, and their gods shall be a snare unto you.

Bible References

I also said

Judges 2:21
I also from now on will not expel any from before them of the nations that Joshua left when he died;
Numbers 33:55
But if you will not drive out the people of the land from before you, then it will be, those of them whom you let remain shall be goads in your eyes and thorns in your sides, and they shall trouble you in the land in which you live.
Joshua 23:13
know for a certainty that Jehovah your God will no more drive out these nations from before you. But they shall be snares and traps to you, and whips in your sides, and thorns in your eyes, until you perish from off this good land which Jehovah your God has given you.

Their gods

Judges 3:6
And they took their daughters to be their wives, and gave their daughters to their sons, and served their gods.
Exodus 23:33
They shall not dwell in your land lest they make you sin against Me. For if you serve their gods, it surely will be a snare to you.
Exodus 34:12
Take heed to yourself, lest you make a covenant with the people of the land where you go, lest it be for a snare in the midst of you.
Deuteronomy 7:16
And you shall destroy all the people which Jehovah your God shall deliver you. Your eye shall have no pity upon them, neither shall you serve their gods, for they will be a snare to you.
1 Kings 11:1
And King Solomon loved many foreign women, even the daughter of Pharaoh, Moabites, Ammonites, Edomites, Sidonians, Hittites;
Psalm 106:36
And they served their idols, which were a snare to them.

General references

Deuteronomy 6:19
to cast out all your enemies from before you, as Jehovah has spoken.
Deuteronomy 20:18
so that they may not teach you to do according to all their abominations which they have done to their gods. So you would sin against Jehovah your God.
Deuteronomy 28:43
The stranger within you shall get up above you very high, and you shall come down very low.
Judges 2:21
I also from now on will not expel any from before them of the nations that Joshua left when he died;
1 Samuel 8:8
According to all the works which they have done since the day that I brought them up out of Egypt even until this day, works with which they have forsaken Me and served other gods, so they do also to you.