Yahweh prepared a great fish to swallow up Jonah, and Jonah was in the belly of the fish three days and three nights.
A more pertinent question, it seems to this writer, is that of whether Jonah remained alive for that three days and three nights within the belly of the great fish, or if God raised him from the dead upon the occasion of the great fish's vomiting him out upon the dry land.  The record of the prayer which Jonah prayed after being swallowed seems to argue that he was alive; but, since the prayer was only a matter of a very few minutes duration, it falls short of proving Jonah's continued life within the fish's belly for a whole three days and three nights.  Basing argument upon the fact that Jesus Christ certainly was not alive for three days and nights in the tomb, DeHaan did not hesitate to affirm that, "Jonah was dead for three days and three nights, and then was resurrected and sent forth to preach."[37]  The event must be accepted as "a sign from heaven," no matter how it is understood, that is, whether Jonah was maintained alive inside the fish for that extended period, or if he was resurrected after the fish vomited him up.