Although the term μυστηριον already appears in the Pauline
corpus, a development of exegesis as mystery performance does not materialize
in Christian context before Melito. In Justin’s works, the term can be
encountered when the writer claims that prophecies describe future events
through parables, mysteries, and symbols regarding those events (εν παραβολαις η μυστηριοις η εν συμβολοις εργων). This is because, generally, the
Holy Spirit manifests itself through parable and in a hidden way (εν παραβολη δε και παρακεκαλυμμενως).
Furthermore, the incarnation,
according to Justin and Irenaeus, was envisioned as an event which entailed
major exegetical consequences, since Christ came and revealed the obscure words
of the ancient holy writings. To this point, Irenaeus claims that the message
of the good news about Christ was hidden (κεκρυμμενος) in prophecies and symbolized
through types and parables (δια τυπων και παραβολων εσημαινετο), yet their full meaning could be
grasped solely at the time of their fulfilment. (Dragoş Andrei Giulea, Pre-Nicene
Christology in Paschal Contexts: The Case of the Divine Noetic Anthropos [Supplements
to Vigiliae Christianae Texts and Studies of Early Christian Life and Language
123; Leiden: Brill, 2014], 198-99)