Mat 10:17 But beware of men: for they will deliver you up to the councils, and they will scourge you in their synagogues;
Mat 10:18 And you shall be brought before governors and kings for my sake, for a testimony against them and the Gentiles.

"Beware" is the Greek prosecho, which means "hold to," "offer," or "to turn you mind toward," or "pay court to." But with apo (the term translated as "of") its meaning changes to "be on guard against." Apo is a term of separation, something like we would use the word "from."

"Deliver you up" is paradidomi , which literally means "to give over." "Councils" is sunedrion, which is the generic Greek term for council that the name of the great Jewish coucil, the Sanhedrin was taken from. "Synagogues" is from the Greek sunagoge, which means "a bringing together."

"Shall be brought" is ago, which means "to lead," "to carry," or "to fetch." "Governors" is from the Greek hegemon, which is a leader of any kind, but a term specifically used for the governors of provinces in Roman times. "Kings" is from basileus, which means a "king" or "chief." "Testimony" is marturion, which means "testimony" or "proof." "Gentiles" is ethnos, that is, "ethnics."

The most important word in the second version is one that DOESN'T appear in the original Greek. There is not Greek term "against" in the phrase.

Together, both verses say, "Be on your guard against men for they will give you to councils and scourge you in their meetings and you shall be led to governors and kings for my sake as their proof and the foreigners."

What is notable here is that it is the groups of people who are dangerous. These groups have to justify themselves before their rulers, but these rulers are not condemned in the Greek as they are they seem to be in the English. It is the mobs of men who are dangerous. This is very consistent with Christ's view of the inherent flaws in human society. Individuals can be good, but they have to be sought out. Society is dangerous.