The sacristy altar has significant historical relevance to this church, as it was in front of it that, on November 4, 1775, 20 years after the earthquake, a solemn Te Deum was celebrated in thanksgiving for the reconstruction of the church. The altarpiece features a Holy Family by Bruno José do Vale, painted in 1775. For this work, the painter uses as a model the Holy Family commissioned by D. João V to Masucci for the Basilica of Mafra. In addition to the Virgin Mary with the Child Jesus on her lap, the figure of John the Baptist, also a child, stands out, who, on the phylactery that hangs from the cross he holds, announces the presence of the Lamb of God (Ecce Agnus Dei). Present in the scene, in the background, are his parents, Elizabeth, Mary’s cousin, and Zechariah. On the left side, still in the background, appears the beloved disciple, the Evangelist Saint John. In the foreground, we see Saint Anne and Saint Joachim, parents of Mary and grandparents of Jesus. The image is surmounted by representations of God the Father and the Holy Spirit, revealed by the dove. The verticality of the compositional line, which encloses the three Persons of the Holy Trinity, links this existence on two levels – the divine and the earthly.