E. Cobham Brewer 18101897. Dictionary of Phrase and Fable. 1898.
The table near the altar on which the bread and wine are deposited before they are consecrated. In former times food was placed on a credence-table to be tasted previously to its being set before the guests. This was done to assure the guests that the meat was not poisoned. The Italian credenzare means to taste meats placed on the credenza. (Italian, la credenza, a shelf or buffet; Greek, kreas, food.)