We are grateful to Dr. Hans Vlieghe for confirming the attribution on the basis of photographs.
Herman Joseph van der Poorter of Bois-le-Duc (Den Bosch) was Abbot of Saint Michael's from 1676 to 1681. The Norbertine or Premonstratensian monastic order (the 'White Canons') was founded in 1120 by Saint Norbert of Xanten, and enjoyed a special veneration in Antwerp, for it was there that Saint Norbert defeated the eucharistic heresy of Tanchelm and founded the Abbey of Saint Michael. In 1624 Rubens completed an Adoration for the upper-choir altar of the Abbey church (now Antwerp, Koninklijk Museum voor Schone Kunsten). The Abbey was partly demolished by Napoleon during the French Revolution in 1797 to make way for a military shipyard, and during the Belgian Revolution in 1830 the rest of the old Antwerp landmark was destroyed.