The cost of evil.

"... but I will recompense their wicked doing upon their own heads." 

-Ezekiel 9:10

Yes, revenge and anger will flow through your mind when you come across vindictive, hurtful, hateful, lewd, wicked, or spiteful people.  However, your line of duty is to immediately pass that person, or those people, over to God; pray for them, forgive them and walk away!  

Remember, you have much better things to do and live for anyway!