What would make God wrathful?
Your sin. My sin.
If you really don know, go here and enter "wrath" http://bible.gospelcom.net/
It's only mentioned 194 times.
My teachers used to say that there is no such thing as a dumb question, but after seeing this one I'm not so sure. Nothing "makes" God do what He does or be anything other than Who He is.
Cordially,