 The Chapel of Saint Isidore ( Spanish : Capilla de San Isidro ) was originally built as an annex between 1624 and 1627 , and was once used as the baptistery . Its vault contains plaster casts representing Faith , Hope , Charity , and Justice , considered to be basic values in the Catholic religion . After the Tabernacle was built , it was converted into a chapel and its door was reworked in a churrigueresque style . 
