Pier Francesco Mola, 'Saint John the Baptist preaching in the Wilderness', about 1640

Saint John the Baptist sits on a rock in a wooded landscape, preaching to a group of people in Oriental dress. According to the Gospel of Luke (3: 1–17), John spent some years living as a hermit in the wilderness, preaching repentance and baptising people in the river Jordan. He was traditionally shown bearded and unkempt, dressed in animal skins and with a cross made of reeds. His followers thought he might be the Messiah, but he told them that he was merely the precursor of Jesus: here he makes this clear by pointing to the slightly ghost-like figure of Jesus in the background.

This small painting is characteristic of Pier Francesco Mola, who specialised in classicising scenes drawn from mythology, the Bible and poetry, set in landscapes inspired by north Italian art. He spent most of his life in Rome, where his father was architect to the Papal Treasury.

Mola painted several variants of this subject – a later one, of about 1650–55, is in the Museo Nacional Thyssen-Bornemisza, Madrid. His art is a fusion of influences, many of which he may have come into contact with in Rome. The motif of the Baptist pointing to the distant figure of Christ suggests his awareness of a fresco by Domenichino in S. Andrea della Valle as well as a painting of the same subject by Veronese, in the collection of Cardinal Scipione Borghese in Rome in the early seventeenth century, which includes a similar crowd of bystanders in Oriental costumes (now in the Galleria Borghese, Rome).

The most important influence here, however, is that of Guercino. The picture’s naturalism, lighting and tightly cropped composition are all characteristics shared by works of Guercino’s including his Dead Christ mourned by Two Angels, while the Baptist’s head echoes that of Saint Thomas in The Incredulity of Saint Thomas. Both works today are also in the Gallery’s collection.