'Beware' in the Bible

"But beware of doing your good actions in the sight of men, in order to attract their gaze; if you do, there is no reward for you with your Father who is in Heaven.

"Beware of the false teachers--men who come to you in sheep's fleeces, but beneath that disguise they are ravenous wolves.

But beware of men; for they will deliver you up to appear before Sanhedrins, and will flog you in their synagogues;

and when Jesus said to them, "See to it: beware of the yeast of the Pharisees and Sadducees,"

How is it you do not understand that it was not about bread that I spoke to you? But beware of the yeast of the Pharisees and Sadducees."

"Beware of ever despising one of these little ones, for I tell you that in Heaven their angels have continual access to my Father who is in Heaven.