The dome on the building is 13.5 metres in diameter and topped with a steeple. The circular interior is decorated with garlands, draperies and pilasters. Underneath is a very beautiful crypt with a circular vault supported by a central pillar. The convent was destroyed after the Revolution. This church as well as the Pentemont church were allocated by Bonaparte to Reformed worship as early as 1802. It was called Temple Sainte-Marie and the name was changed to Temple du Marais a few years ago.
The parish joined the United Protestant Church of France and is now thriving, as worship takes place on Sundays once in the morning and twice in the afternoons. An evangelical service in Arabic and a service in Japanese are also held on Sunday afternoons.
Since July 2013 two pastors have been appointed to the Temple du Marais.
Every week young people sing Gospel songs. The crypt sometimes houses temporary exhibitions.