A macro is more appropriate for what you are lookign to do. Look at the bottom for class specific links to macros because you did not specify your class: http://www.wowwiki.com/Macros

My RandomSay addon, available here on Curse, may be of help.  You'd install it, then create a macro like:

#showtooltip

/rs What, you died again?  You don't get frequent dier miles for this, you know.../Come back to life, or undeath if you're a Death Knight, or... oh heck, just move already!/Sorry, but death is no excuse for lying down.

/cast resurrection

Basically, you just separate the strings you want it to be able to say with slashes.  If you don't want it to do it all the time, you can put in a chance, like so:

/rs 20 thing1/thing2

has a 20% chance to say something, and will pick either thing1 or thing2 to say.

There's also a "/rem", if you'd rather emote something.

On my priest I use Priest Friend. It does a ton of random sayings on Res and I never fail to get a laugh from group members.

Priest Friend - http://wow.curse.com/downloads/wow-addons/details/priestfriend.aspx