No way back
One has to be certain of the journey that they are embarking on, be it by faith or adequate information, before they burn the bridges from where they are coming from.
Is it always necessary to burn bridges? I think this depends on the individual. There are very strong willed people who can walk out of a situation and they will never turn back. But there are others who need to make it dramatic, not because they love drama, but because they know that if they don’t take a very public stand and burn those bridges, they will be back to those things they are trying to walk away from in a heartbeat.
Sometimes we must only walk away for a season, sometimes it is final. Whatever the situation, know yourself, and make sure you are very convinced that it is the time to walk away because once you burn that bridge, there will be no way back.