In general style, this picture is strongly Italianate showing the influence of the Italianising Barent van Orley to whom it had previously been attributed. This would suggest that the painting is a relatively early work, from the 1530s before the artist arrived in Spain in 1537. The Tiburtine Sibyl was the tenth and last in the group of ancient Greek figures.  Curiously enough, they became part of Christian mythology. The Roman Emperor Augustus (63BC – AD14) had been declared a living god by the Roman Senate. The Emperor then consulted the Sibyl who predicted the birth of Jesus Christ, and at the same time a heavenly vision of the Virgin and Child opened up to the pagan Emperor. This mythical incident was taken up by Christian artists and writers.

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