The word "God" may mean different for different people. For some it may be an unimaginable mysterious power, idol and pictures for others, some may believe nature and sun, moon or energy, fire or water for some. But whatever it may be, one thing common between them is that they remember that representation to gather strength and hope during their difficult times. If god of bible is such a representation for me whom i think about during difficult times, then yes i believe in it.