This verb means to doubt or waver, suggesting division or hesitation in the mind. The root connection to 'twice' or 'double' implies being pulled in two directions. Matthew uses it twice: Jesus asking Peter why he 'doubted' while sinking (14:31), and noting that some disciples 'doubted' even when seeing the risen Christ (28:17). Both contexts involve faith challenges in supernatural moments—walking on water and resurrection appearance. The term captures the internal division between faith and fear, belief and uncertainty. Spanish 'dudaste' (did you doubt) and French 'douter' directly render this wavering between alternatives, this being of two minds.