Without the courage to doubt, Christians (and the same applies to many other religious believers) cannot do what we are called to do.
In times of suffering, people doubt not merely the existence of God, but their entire worldviews. We are called to comfort those who suffer. But we cannot do so with the confidence of Job’s friends, sure that our theologies are correct and that our role as comforters is to make sure the sufferer’s theology does not change in the process of suffering. We are called to draw alongside the sufferer and put our own faith at risk – for that is what it means to share with them in their suffering to the limited extent that we can. If our faith comes out the other side exactly the same way it went in, then we haven’t done it properly.
Sharing our faith is another thing that we are called to do. And likewise, you cannot share your faith with someone who does not adhere to it – and thus doubts at least some major elements of your worldview – without engaging those doubts. Simply asserting that they are wrong is not sharing your faith. To be any good as an apologist for your own viewpoint (and there are so many bad ones these days that the word “apologetics” has come to denote sharing one’s faith in a manner that only those who already accept it would find convincing), you must not merely build bridges to those who doubt what you believe, you must cross those bridges to meet them. Once you are able to view your beliefs from their standpoint of doubt, only then will it become clear whether the best thing to so is to bring them back across the bridge with you – whether all the way or partially – or to both travel on together by a different route.
Doubt is the only way to accomplish some of the most fundamental components of a life of faith lived in the world. If you’ve been shielding your faith from doubt, then you doubt it already. You just don’t doubt it with the courage needed to truly bring it into the world in a way that has the potential to positively transform you and/or others.
For further reading on this topic, I recommend Robert Davidson’s book The Courage to Doubt: Exploring an Old Testament Theme and of course Paul Tillich’s Dynamics of Faith
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