As Jonas was three days and three nights. — To understand the words rightly, we have to remember the prominence which our Lord gives to the history of Jonah, and to the repentance of the men of Nineveh, in this and in the parallel passage of Luke 11:29, and in answer to another demand for a sign in Matthew 16:4. In the other passages “the sign of the prophet Jonas” appears with a vague mysteriousness, unexplained. Not a few critics have accordingly inferred from this difference that the explanation given by St. Matthew was an addition to the words actually spoken by our Lord, and that “the sign of the prophet Jonas” was sufficiently fulfilled by His preaching repentance to the wicked and adulterous generation as Jonah had done to the Ninevites. Against this view, however, it may be urged: — (1) That Jonah’s work as a preacher was not a “sign” in any sense, and that nothing in his history had this character, except the two narratives of the whale (Jonah 1:17) and the gourd (Jonah 4:6-10). Any reference to the latter is, of course, out of the question; and it remains therefore, in any case, that we must look to the former as that to which our Lord alluded. (2) That the very difficulty presented by the prediction of “three days and three nights” as compared with the six-and-thirty hours (two nights and one day) of the actual history of the Resurrection, is against the probability of the verse having been inserted as a prophecy after the event. (3) That if we believe that our Lord had a distinct prevision of His resurrection, and foretold it, sometimes plainly and sometimes in dark sayings — and of this the Gospels leave no room for doubt (Matthew 16:21; Matthew 26:32; John 2:19) — then the history of Jonah presented an analogy which it was natural that He should notice. It does not necessarily follow that this use of the history as a prophetic symbol of the Resurrection requires us to accept it in the very letter of its details. It was enough, for the purposes of the illustration, that it was familiar and generally accepted. The purely chronological difficulty is explained by the common mode of speech among the Jews, according to which, any part of a day, though it were but a single hour, was for legal purposes considered as a whole. An instance of this mode of speech is found in 1 Samuel 30:12-13, and it is possible that in the history of Jonah itself the measurement of time is to be taken with the same laxity.
Some incidental facts are worth noticing: (1) that the word translated “whale” may stand vaguely for any kind of sea-monster; (2) that “the heart of the earth,” standing parallel as it does to “the heart of the seas,” the “belly of hell” — i.e., Sheol and Hades — in Jonah 2:2-3, means more than the rock-hewn sepulchre, and implies the descent into Hades, the world of the dead, which was popularly believed to be far below the surface of the earth; (3) that the parable has left its mark on Christian art, partly in the constant use of Jonah as a type of our Lord’s resurrection, and partly in that of the jaws of a great whale-like monster as the symbol of Hades; (4) that the special character of the psalm in Jonah 2, corresponding as it does so closely (Jonah 2:6) with Psalms 16:10-11, may well be thought to have prompted our Lord’s reference to it.