He confirmed the parallel of Jonah's story as a reference to Himself:
Mat_12:40 For as Jonah was three days and three nights in the belly of the great fish, so will the Son of Man be three days and three nights in the heart of the earth.
In Luk 12:46, for example, Christ referred to Jonah's story as it was written in the OT--not as a literal word-for-word quote of Christ's resurrection but as a parallel reference to His resurrection. As I pointed out with Paul's example, the term "it is written" doesn't always equate to a direct, word-for-word quote from the OT. It can simply be a reference to a story, parallel, or prophecy in the OT.