Reichstag fire was an incident that occurred in February 1933. The Reichstag fire was used by Adolf Hitler to his advantage by blaming the communists. The fire was a catalyst to put fear in the German people that a form of coup was to take place.
The Nazis played this perfectly and made numerous arrests of communists and put the state into a form of panic. It is unclear still as to the origins of the fire but it served as an advantage for the Nazis.
Under article 48 of the Weimar constitution, the president can enforce laws without the need to approve it with the Reichstag. This leads on to enabling act.