If God's Son can be transferred to the womb of a virgin Israelite by means of God's Spirit, surely His Spirit could preserve Jonah in the belly of a fish.
While I may agree with the "muraculous" approach in explaining such events as alegories, there are practical considerations that completely obliterate the possibility of these things occuring in reality.
Jonah STILL needed oxygen, fresh water and protection from digestive acids.
Did the Holy Spirit create a physical barrier inside the whale?
Did the Holy Spirit create oxygen inside said physical barrier? How was the oxygen derived? For someone's life to be sustained for 3 days, X amount of oxygen is needed PERIOD.
Did the Holy Spirit use existing matter to break down and release oxygen, maybe some oxides. Was it an electrolysis using ocean water, if so what was the physical aparatus to achieve it?
I can go on and on.
I KNOW of at least a dozen reazons why this CAN'T be done.
If your answer in the inavoidability of physical limitations is that we, well, DON'T KNOW, then that's what it is.
WE DON'T KNOW.
Let's admit it and until WE KNOW, let's not just say WE KNOW because it's a MIRACLE.....Even miracles are confined within the laws of physics, termidynamics, etc, which make our very existense possible. These laws, whether instituted by God or not, are blind, impartial and unforgiving.