See the description of the chapel, destroyed in the fire of 1734, in
Martínez Leiva, G. and
Rodríguez Rebollo, Á. (
2015)
El inventario del Alcázar de Madrid de 1666: Felipe IV y su colección artística (
Madrid:
Ediciones Polifemo), pp.
87–
88. As regards the effect of the Council of Trent on art, a very influential book was
Discorso intorno alle imagini Sacre e Profane, by the Cardinal Gabriele Paleotti, published in 1582 (available in memofonte.it). Book 2, Ch. 4 deals inter alia with ‘pitture scandalose’, but there is no reference at all to the Virgin pregnant or otherwise. Admittedly, more about the Virgin was to come in a later book never published. About its influence on our present case, it must be remembered that the Cardinal, as Bishop of Bologna, was only addressing his Diocese and even then not in a prescriptive but only in an advisory capacity, as was the case for all bishops. One interesting case is that of the Annunciations showing a Baby on the Holy Spirit’s beam. Paleotti (Book 4, Ch. 6) proscribes them (which in fact disappear after 1600) not on the basis of their naturalism but on sound theological grounds: the Baby they depict would be wholly formed from the Holy Spirit, which would make the incarnation defective, Jesus having to be wholly human, as generated by the Virgin’s blood.
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