Timothy Keller

"People who blithely go through life too busy or indifferent to ask hard questions about why they believe as they do will find themselves defenseless against either the experience of tragedy or the probing questions of a smart skeptic. A persons faith can collapse almost over night if they have failed over the years to listen patiently to their own doubts, which should only be discarded after long reflection. Believers should acknowledge and wrestle with doubts--not only their own but their friends' and neighbors'." "Only if if you struggle long and hard with objections to your faith will you be able to provide grounds for your beliefs to skeptics, including yourself, that are plausible rather than ridiculous or offensive." 

-Timothy Keller

Ask hard questions. Know what you believe. Know why you believe it.