The middle ages classified commentaries on scripture into four categories of interpretation, so that each text could have a literal meaning, an allegorical meaning (drawing the religious lesson), a tropologlcal (moral) meaning and an anagogical (mystical) meaning. The four-fold possibility of each text was summarized in the famous rhyme.
Litteragesta docet; quid credas allegoria;
Moralis, quid agas; quid speres, anagogia.
The Enchiridion contains several examples of the allegorical exegesis of the Old Testament.
N.B. The words 'allegorically, tropologically, and anagogically' were added to the text in 1522.