Religious belief is not set in stone. Faith is a bond of trust between a person and what they have chosen to believe and can therefore wax and wane or even lead to a person abandoning all of their religious principles amid a spiritual crisis. But is religious doubt something to fear and avoid? Can a crisis of faith be used to look deeper into the basic tenets of your chosen religion, restoring your bond with it or giving you the strength to turn to a new set of beliefs and morals? Shifu Ming Hai talks us through the positive aspects of doubt with, as ever, Zen Buddhism as his guide.