Judges 2:3

Wherefore I have likewise determined that I will not cast them out before you: that they may be a fall unto you, and their gods shall be snares unto you."

Numbers 33:55

But and if ye will not drive out the inhabiters of the land before you, then those which ye let remain of them, shall be thorns in your eyes and darts in your sides, and shall vex you in the land wherein ye dwell.

Joshua 23:13

be sure that the LORD your God will not cast out all these nations before you. But they shall be snares and traps unto you, and scourges for your sides, and pricks in your eyes, until ye perish from off this good land which the LORD your God hath given you.

Deuteronomy 7:16

Thou shalt bring to nought all nations which the LORD thy God delivereth thee; thine eye shall have no pity upon them neither shalt thou serve their gods, for that shall be thy decay.

Judges 2:21

therefore henceforth I will not cast out one man before them of the nations which Joshua left when he died -

Judges 3:6

they took the daughters of them to be their wives, and gave their own daughters to their sons, and served their gods.

Psalm 106:36

insomuch that they worshipped their idols, which turned to their own decay.

Exodus 23:33

Neither shall they dwell in thy land, lest they make thee sin against me: for if thou serve their gods, it will surely be thy decay."

Exodus 34:12

Take heed to thyself, that thou make no covenant with the inhabiters of the land whither thou goest lest it be cause of ruin among you.

1 Kings 11:1-7

But king Solomon loved many outlandish women: the daughter of Pharaoh, and of the Moabites, Ammonites, Edomites, Sidonians and 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
therefore henceforth I will not cast out one man before them of the nations which Joshua left when he died -
Numbers 33:55
But and if ye will not drive out the inhabiters of the land before you, then those which ye let remain of them, shall be thorns in your eyes and darts in your sides, and shall vex you in the land wherein ye dwell.
Joshua 23:13
be sure that the LORD your God will not cast out all these nations before you. But they shall be snares and traps unto you, and scourges for your sides, and pricks in your eyes, until ye perish from off this good land which the LORD your God hath given you.

Their gods

Judges 3:6
they took the daughters of them to be their wives, and gave their own daughters to their sons, and served their gods.
Exodus 23:33
Neither shall they dwell in thy land, lest they make thee sin against me: for if thou serve their gods, it will surely be thy decay."
Exodus 34:12
Take heed to thyself, that thou make no covenant with the inhabiters of the land whither thou goest lest it be cause of ruin among you.
Deuteronomy 7:16
Thou shalt bring to nought all nations which the LORD thy God delivereth thee; thine eye shall have no pity upon them neither shalt thou serve their gods, for that shall be thy decay.
1 Kings 11:1
But king Solomon loved many outlandish women: the daughter of Pharaoh, and of the Moabites, Ammonites, Edomites, Sidonians and Hittites,
Psalm 106:36
insomuch that they worshipped their idols, which turned to their own decay.

General references

Deuteronomy 6:19
and that the LORD may cast out all thine enemies before thee as he hath said.
Deuteronomy 20:18
that they teach you not to do after all their abominations which they do unto their gods, and so should sin against the LORD your God.
Deuteronomy 28:43
The strangers that are among you shall climb above thee up on high, and thou shalt come down beneath a-low.
Judges 2:21
therefore henceforth I will not cast out one man before them of the nations which Joshua left when he died -
1 Samuel 8:8
And as they have ever done - since I brought them out of Egypt unto this day, and have forsaken me and served other gods - even so do they unto thee.