The Mirror Room has had different functions throughout time. Before the sixteenth century, it was part of the Sacristy and later it became the place where the commissioners of marital affairs held office. During that period, Rembrandt van Rijn, among others, went there with Saskia van Uylenburgh to get betrothed. Like the rest of the church, the room is a mixture of elements from different eras that never existed at the same time.
Standing in the Mirror Room, you find yourself in a multicoloured painting full of flowers and birds. It is one of the Oude Kerk’s most elegant side rooms. The colourfully painted linen wall coverings adorn almost all of the walls and doors. The wallpaper was made around 1760 - 1770, as were the wood carvings with shell motifs and the large mirror with its gilded frame. What the room looked like before that time is largely unknown. Similar wallpapers with large floral and bird motifs on a light blue background were common in 18th century houses. Only a small number of them have survived to this day. Remarkable about the wallpaper in the Mirror Room is the use of silver and golds. In a number of flowers, their heart or the entire flower, is first coated with sheet metal (gold or silver) and subsequently painted with transparent lacquers. In addition to the use of sheet metal, it is notable that on this wallpaper the flowers are not attached to ascending tendrils, but the tendrils are scattered loosely across the surface. The flowers themselves are largely painted realistically. Among others, imperial crowns, primroses, tulips, roses and oriental cress are recognizable. The leaves of the tendrils to which the flowers are attached do not correspond to the leaves belonging to these flowers. For the leaves, a combination was made between different leaf shapes inspired by acanthus, ivy or lathyrus, among others.
The canvas to which the coverings are affixed has started to sag because the ancient frames are worn out. The paint is peeling in various places as well, and a thick layer of dust, overpaintings and restorations are obscuring the wall coverings from view. Damages and previous restorations have caused the coverings to lose their original lustre. After extensive research into the history and condition of the eighteenth-century wall coverings was carried out, they were restored to their former glory and preserved for future generations as best as possible. In the course of this restoration work, three canvases of older wallpaper were discovered in an attic above the Church Warden’s Chamber. One of the canvases shows laurel wreaths, floral garlands, and a vase on cream-coloured ground. It is, however, in an advanced state of decomposition. The other two canvases show arcadian landscapes with human figures on a light blueish-green ground, framed by blue rocaille ornaments. Due to their dimensions, it is to be assumed that they originally adorned the walls next to the Mirror Room's fireplace as well as the reception room next to it, nowadays part of the Koffieschenkerij.
