Scripts for beginners.

Please, someone help me :)

I've just started learning scripting, so I don't quite understand why the following code isn't working for me:(

function f1()
       MessageBox("The Prophet does not wish to see you.")
end
SetObjectEnabled("Prophet", nil)
Trigger(OBJECT_TOUCH_TRIGGER, "Prophet", 'f1')

SetObjectEnabled works as expected, but the Trigger doesn't. What's wrong?