I think being rational is using reason, science and logic to come to good sound conclusions. They are irrational because they rely on "faith". They (theists) believe for the sake of believing. What is your position Blossom?
"I trust my own reason and my own capacities to think and educate myself and to reach greater levels of knowlege and status through learning and work. To me, wishing for a god is like wishing to be a slave, it is like declaring that one is too incompetent to handle one's own affairs." - the germans are coming