This chapel was built in the early 18th century, in a slightly secluded position, compared to the other two. The group of sculptures represents Abraham, in a luxuriant garden, kneeling before three Angels, who are the symbols of the mystery of the Trinity. The scene shows the meeting between Abraham and the angels, at the oaks of Mamre, as told in the Genesis (Gen. 18, 1-10). The patriarch and his wife Sara welcome three mysterious guests, and offer them food and water. On the right, the tent of the biblical tale is transformed into a house, from which two figures are watching the scene. The statues of two Prophets are witnessing from the side niches.
