Judges 2:3

And I also have said, I do not cast them out from your presence, and they have been to you for adversaries, and their gods are to you for a snare.'

Numbers 33:55

And if ye do not dispossess the inhabitants of the land from before you, then it hath been, those whom ye let remain of them, are for pricks in your eyes, and for thorns in your sides, and they have distressed you on the land in which ye are dwelling,

Joshua 23:13

know certainly that Jehovah your God is not continuing to dispossess these nations from before you, and they have been to you for a gin, and for a snare, and for a scourge, in your sides, and for thorns in your eyes, till ye perish from off this good ground which Jehovah your God hath given to you.

Deuteronomy 7:16

And thou hast consumed all the peoples whom Jehovah thy God is giving to thee; thine eye hath no pity on them, and thou dost not serve their gods, for a snare it is to thee.

Judges 2:21

I also continue not to dispossess any from before them of the nations which Joshua hath left when he dieth,

Judges 3:6

and take their daughters to them for wives, and their daughters have given to their sons, and they serve their gods;

Psalm 106:36

And serve their idols, And they are to them for a snare.

Exodus 23:33

they do not dwell in thy land, lest they cause thee to sin against Me when thou servest their gods, when it becometh a snare to thee.'

Exodus 34:12

take heed to thyself, lest thou make a covenant with the inhabitant of the land into which thou art going, lest it become a snare in thy midst;

1 Kings 11:1-7

And king Solomon hath loved many strange women, and the daughter of Pharaoh, females of Moab, Ammon, Edom, Zidon, and of the 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 continue not to dispossess any from before them of the nations which Joshua hath left when he dieth,
Numbers 33:55
And if ye do not dispossess the inhabitants of the land from before you, then it hath been, those whom ye let remain of them, are for pricks in your eyes, and for thorns in your sides, and they have distressed you on the land in which ye are dwelling,
Joshua 23:13
know certainly that Jehovah your God is not continuing to dispossess these nations from before you, and they have been to you for a gin, and for a snare, and for a scourge, in your sides, and for thorns in your eyes, till ye perish from off this good ground which Jehovah your God hath given to you.

Their gods

Judges 3:6
and take their daughters to them for wives, and their daughters have given to their sons, and they serve their gods;
Exodus 23:33
they do not dwell in thy land, lest they cause thee to sin against Me when thou servest their gods, when it becometh a snare to thee.'
Exodus 34:12
take heed to thyself, lest thou make a covenant with the inhabitant of the land into which thou art going, lest it become a snare in thy midst;
Deuteronomy 7:16
And thou hast consumed all the peoples whom Jehovah thy God is giving to thee; thine eye hath no pity on them, and thou dost not serve their gods, for a snare it is to thee.
1 Kings 11:1
And king Solomon hath loved many strange women, and the daughter of Pharaoh, females of Moab, Ammon, Edom, Zidon, and of the Hittites,
Psalm 106:36
And serve their idols, And they are to them for a snare.

General references

Deuteronomy 6:19
to drive away all thine enemies from thy presence, as Jehovah hath spoken.
Deuteronomy 20:18
so that they teach you not to do according to all their abominations which they have done to their gods, and ye have sinned against Jehovah your God.
Deuteronomy 28:43
the sojourner who is in thy midst goeth up above thee very high, and thou goest down very low;
Judges 2:21
I also continue not to dispossess any from before them of the nations which Joshua hath left when he dieth,
1 Samuel 8:8
According to all the works that they have done from the day of My bringing them up out of Egypt, even unto this day, when they forsake Me, and serve other gods -- so they are doing also to thee.