Upvote:1
The monk mentioned by the O.P. sounds like Joachim of Fiore (c. 1135 – 1202) to me. He was active mostly during the 12th century, but he did make it to the 13th.
Some of his ideas about the nature of the Holy Trinity were refuted posthumously by the Fourth Lateran Council (1215).
However, his doctrine of the “three ages” is a bit different from what the O.P. States. According to Joachim,
(See the Wikipedia article for a summary.)