The painting has lost weight
The first step in treating "Christ Driving the Money-lenders from the Temple” was to thin the wood “cradle” construction that had been attached to the back of the panel during a previous treatment. The cradle was made of mahogany and consisted of horizontal battens, which were glued to the reverse of the panel, with moveable wooden battens inserted through holes in the horizontal battens. See photo of the painting's back before treatment. The mahogany construction was heavy and had seized up, restricting the movement of the original panel and causing it to develop a concave warp.
In order to make the painting easier to handle and transport, and to allow the original timber the freedom to move relative to the surrounding environment, the whole mahogany construction was thinned. This process involved removing the jammed wooden battens, cutting into the “bridges” of the static battens, before reducing them in height so that only a series of mahogany blocks remained. Some of these were left thicker to support joints and cracks in the original panel. The vertical, moveable battens were also thinned, and were reattached with flexible clamps. The original panel now has the possibility of moving in response to climate changes, but the modified cradle structure on the back still provides support for the painting.