This is from Cyril’s “Catechism” and is an interesting point:
Τούτου τοῦ σωτῆρος ἡμῶν τὸν τύπον ἐτέλει ὁ προφήτης Ἰωνᾶς ἐκ κοιλίας κήτους προσευχόμενος καὶ λέγων ἐβόησα ἐν θλίψει μου, και ἑξῆς, ἐκ κοιλίας ᾅδου. καὶ μὴν ἐν τῷ κήτει ἧν.
ἀλλ’ ἐν τῷ ᾅδῃ ἑαυτὸν εἶναι λέγει. τύπος γὰρ ἦν Χριστοῦ τοῦ μέλλοντος εἰς ᾅδην καταβαίνειν. καὶ μετ’ ὀλίγα φησὶν ἐκ προσώπου τοῦ Χριστοῦ λευκότατα προφητεύων· ἔδυ ἡ κεφαλή μου εἰς σχισμὰς ὀρέων. καὶ μὴν ἐν γαστρὶ κήτους ἦν.
The prophet Jonah fulfilled the type of our of savior, lifting up prayers from the belly of the sea-monster and saying, “I cried out in my affliction” and then, “out of the belly of Hades”, even though he was in the sea-monster.
And he says that he is himself in Hades. For this type was of Christ, the one about to descend into hades, and (I’m having a little trouble with this part) after a few things he spoke, prophesying the most plain things from the person of Christ (?): “My head is plunged into the cliffs of mountains” even though he was in the belly of the sea-monster.