A former 16th-century malthouse in Church Street in the old quarter of the town, the restaurant is near St Illtud's Church, which provides half of its name.
The second half is based on the numerals 216, which were uncovered everywhere on the walls during restoration under the previous owner and are believed to be the number of the devil (being the sum of 6 x 6 x 6).
It offers a 55-seat restaurant, a separate bar area, three-bedroom owners' accommodation and a private garden.
The Bristol office of Christie + Co sold the freehold off a guide price of £595,000 on behalf of Andrew Davies, who will now focus on his Horseshoe Inn at nearby Marcross.
By Angela FrewinFormer St David's hotel executive chef buys first restaurant >>