2 Timothy 4:15

But be on the watch for him, for he was violent in his attacks on our teaching.

Matthew 10:16-17

See, I send you out as sheep among wolves. Be then as wise as snakes, and as gentle as doves.

Philippians 3:2

Be on the watch against dogs, against the workers of evil, against those of the circumcision:

2 Timothy 3:8

And as James and Jambres went against Moses, so do these go against what is true: men of evil minds, who, tested by faith, are seen to be false.

Treasury of Scripture Knowledge

Summary

Of whom be thou ware also; for he hath greatly withstood our words.

Bible References

Be

Matthew 10:16
See, I send you out as sheep among wolves. Be then as wise as snakes, and as gentle as doves.
Philippians 3:2
Be on the watch against dogs, against the workers of evil, against those of the circumcision:

Basic English, produced by Mr C. K. Ogden of the Orthological Institute - public domain