The Feast of St. Augustine of Hippo, 28th August [I Am Roman Catholic]
"He is thy best servant who does not look to hear from thee what he himself wills, but who wills rather to will what he hears from thee."
Optimus minister tuus est, qui non magis intuetur hoc a te audire quod ipse voluerit, sed potius hoc velle quod a te audierit.
St. Augustine, Confessions X.26

Or - in pithy words a bit more familiar to our own age:
Ask not what God can do for you - ask what you can do for God.
Sancte Augustine, ora pro nobis.
Optimus minister tuus est, qui non magis intuetur hoc a te audire quod ipse voluerit, sed potius hoc velle quod a te audierit.
St. Augustine, Confessions X.26

Or - in pithy words a bit more familiar to our own age:
Ask not what God can do for you - ask what you can do for God.
Sancte Augustine, ora pro nobis.