Interpretation
It is a statement by the Protestant Spenser against the extensive use of images by the Roman Catholic Church. It also carries the implication of "Arch Mage", "Arch Magician." Disguised as a reverend hermit, and by the help of Duessa or Deceit, he seduces the Red-Cross Knight from Una or Truth.
Book 1, Canto XII, lines 303 and 305 describe Archimago as "clokt with simpleness". Much of the The Faerie Queene is allegory, reflecting the religious/historical framework of 16th century England. Thus the "cloak of simpleness" may refer to monks' garb, or more specifically to the monks themselves, whom Spenser and Protestant England did not tolerate. Furthermore, the iconoclastic Dissolution of the Monasteries links the monks to iconography, just like Archimago's name.
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