What is Faith

I really enjoyed this quote from John Pearson’s quote of the day:

 
"Faith, if you like, can be defined like this: It is a man insisting upon thinking when every thing seems determined to bludgeon and knock him down. The trouble with the person of little faith is that, instead of controlling his own thought, his thought is being controlled by something else, and, as we put it, he goes round and round in circles. That is the essence of worry. That is not thought; that is the absence of thought, a failure to think."  – Martyn Lloyd-Jones