In situ H-1 MAS NMR spectroscopy of the proton, transfer between bridging hydroxyl groups and benzene molecules yields temperature-dependent exchange rates over more than five orders of magnitude. H-D exchange and NOESY MAS NMR experiments were performed by conventional and laser heating up to 600 K. It is shown that the dealumination of the zeolite has a strong influence on this exchange rate, which represents a dynamic measure of Bronsted acidity.