What is common between the three faiths should help us understand each other and 'live and let live'.
But the differences are not unimportant. The Bible says you can mass murder innocents in order to conquer their land for God, or burn witches, believe we are all sinners destined for hell if we do not accept the death and resurrection of Jesus.
I know how to live with my neighbor because I know right from wrong which is reinforced by the teachings of the Quran. This is full of principles about human rights which come into conflict with the beliefs of others so how do we move forward? Compromise and let them do wrong, or speak the truth and cause anger in them? The Quran says speak the truth and do justice even against onself, so I know what i must do.