The use of woodcarving in very large surfaces within Catholic churches was very usual in the 17th and 18th century not only in Portugal and Spain but also in Southern America, and in other European Catholic countries. In Portugal, the town of Porto was even well known for its informal school of woodcarving masters. This paper presents the results for sound absorption coefficients regarding a typical early 18th century baroque woodcarving church piece. A large chestnut-tree wood altarpiece (about 21 m) from the Portuguese church of the Monastery of the Saint John the Evangelist of Vilar de Frades (near the northern town of Barcelos) was tested. That "Retable of the Purgatory Souls" was carefully removed from the church during a large renovation program and tested in a reverberant chamber using one-third octave bands from 100 Hz to 5000 Hz. These results show a sound absorption coefficient of about 0.3 and not very dependent on frequency. This paper also presents the acoustic measurements regarding reverberation time done within that church with and without many areas of woodcarving, from 125 Hz to 4000 Hz and without occupancy. [Partly supported by the IPPAR The Portuguese National Institute for the Architectural Patrimony]