Catechism number 2732

The most common yet most hidden temptation is our lack of faith. It expresses itself less by declared incredulity than by our actual preferences. When we begin to pray, a thousand labors or cares thought to be urgent vie for priority; once again, it is the moment of truth for the heart: what is its real love? Sometimes we turn to the Lord as a last resort, but do we really believe he is? Sometimes we enlist the Lord as an ally, but our heart remains presumptuous. In each case, our lack of faith reveals that we do not yet share in the disposition of a humble heart:
"Apart from me, you can do nothing."²⁰