Matthew 12:40 ESV
For just 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.
To those who believe Jonah was alive, how did Jesus do the sign of Jonah if Jesus was dead for three days and nights, but Jonah was alive?
There are several intriguing similarities between the Jonah account and what happened to Jesus, though it is understood that Jonah was initially disobedient to God, while Christ never was. However, consider these points:
In the tempest, the sailors fired one question after another at Jonah. "Who are you?" "What is your mission?" Death faced Jonah for his honest answers, and he knew it. Jesus was questioned, and he knew death faced him no matter how he answered, but he never lied. Jonah had lots cast over him. So did Christ. Jonah was given over to death, that the sailors might live. Christ was sacrificed that we sinners might live. The Lord's salvation was worked out through Jonah, and supremely through Christ.
Ah, but you note that Jonah never actually died while in the belly of the great fish, yet Jesus actually died. This is the point of your question, suggesting to you that Jesus never actually "completed" the sign of Jonah. The idea seems to be that Jesus should never actually have died if the parallel was to remain intact.
However, it is already obvious that the Jonah account was never meant to be an exact parallel for what would happen to Jesus. Jonah was trying to run away from God, to disobey God's will for him. That could never be said of Christ, who came to do God's will as written in "the book" about him. Jesus took Jonah to be a historic character with real events, but note how Jesus restricted himself in what parallels he drew out?
Jesus knew Jonah never died then, but Jesus knew that he would, therefore he never mentioned Jonah, or himself, being dead for [part of] three days. He stuck to being "in the heart of the earth". We all know Jonah was in the sea, not the earth. No attempt is being made by Jesus to exactly parallel events. The critically important point is that what befell Jonah was God's punishment on him for his sin, bringing him as close to death as possible without actual death. But with Christ, he would actually have to die as God's judgment and punishment on sin was poured out on him during the darkness of Golgotha.
Just as God prevented Isaac the son being sacrificed, providing another sacrifice, this pointed to Christ, his Son, as the ultimate sacrifice. Isaac was "a shadow" of Christ, teaching a massive lesson, yet Isaac only came as close to death as God would permit. Christ was the reality, and really had to die as a sacrifice, though he was without sin. So, with Jonah. He pointed symbolically to the coming Christ. Jonah only came as close to death as God would permit. He permitted the actual death of his Son, because those old testament events were 'types', illustrating some vital truths about God's plan of salvation. Not every detail had to be paralleled; indeed, they could not be. Let me conclude by quoting from this scholar's study-book on the Bible book of Jonah:
"The Lord wished Jonah's punishment to be as close as could be to that of dying without actual death. Because of this Jesus was able to draw out the parallel with his own death, involving the punishment for sin, and also the fact that after the experience there was a resurrection to come. This was to give his followers a frame of reference and hope when they came to grapple with the reality of the cross...
...the definitive interpretive word of Jesus himself [bringing out] various truths in the incident.. for instance, the heinousness of rebellion against God, death as the appropriate penalty for this, the fact that God is able to rescue from death, and that his grace and salvation are capable of offsetting even the most atrocious of sins. Indeed these were lessons that Jonah and his contemporaries were expected to learn from the prophet's experience." Jonah, Micah, Nahum, Habakkuk and Zephaniah, John L. Mackay, p.32, Christian Focus, 1998
Jesus surpasssed the sign of Jonah, for sinful Jonah was being punished for his own sin, while the Son of God was being punished for our sins.
Background information: God commanded Jonah to go to the city of Nineveh and warn its people that He was going to destroy it for its wickedness. Jonah didn’t want to go to Nineveh to warn them. Instead, he ran off in the opposite direction and headed for the city of Tarshish by boat. God then sent a severe storm that caused the crew of the ship to fear for their lives. The crew threw Jonah overboard and he was swallowed by a great fish where he remained for “three days and three nights” (Jonah 1:15–17). After the three-day period, God caused the great fish to vomit Jonah out onto dry land (Jonah 2:10). There is no indication that Jonah was dead during this period of time.
The phrase “sign of Jonah” was used by Jesus as a typological metaphor for His future crucifixion, burial, and resurrection: Shortly after the Pharisees accused Jesus of driving out demons by the power of Satan, they said to Him,
Teacher, we want to see a sign from you.” He answered, “A wicked and adulterous generation asks for a sign! But none will be given it except the sign of the prophet Jonah. For as Jonah was three days and three nights in the belly of a huge fish, so the Son of Man will be three days and three nights in the heart of the earth. The men of Nineveh will stand up at the judgment with this generation and condemn it; for they repented at the preaching of Jonah, and now something greater than Jonah is here (Matthew 12:38–41).
Jesus refused to give the Pharisees further proof of His identity, but He did say that there would be one further sign forthcoming – His resurrection from the dead. This was a far greater miracle than Jonah’s life being spared.
The key message to the unbelieving Pharisees was that the sinful people of Nineveh repented, and they would be there at the judgment to condemn the sinful and unrepentant people of Jerusalem. After Jonah learned his lesson and brought God’s warning to the people of Nineveh, they repented of their evil ways (Jonah 3:4–10). On the other hand, the Pharisees continued in their unbelief despite being eyewitnesses to the miracles of Jesus.
If we direct a fish-eye lens at Scripture, we can see more of what this sign of Jonah means. Here is a link to a wonderful illustration:
Christ Fishing for the Leviathan, c. 1700
The picture shows Jesus as both fisherman and bait! Jesus is the bait use to "draw out Leviathan with a fishhook" as proposed by God in Job 41:1.
By comparison, the fish that swallowed Jonah is a concrete metaphor for the evil empire Leviathan, the "beast from the sea" of Revelation 13.
If you read Job 41, you will see many parallels between the imagery and the sufferings of Christ. So just as Jonah became fish food, Jesus became bait to catch an evil empire and subdue it. The parallel empire in Jonah is Assyria, another prophetic beast whose wickedness was restrained by repentance at Jonah's preaching.
OP: To those who believe Jonah was alive, how did Jesus do the sign of Jonah if Jesus was dead for three days and nights, but Jonah was alive?
The Ignatian longer recension to the Traillians understood the simile not as referring to life/death necessarily, but as to position. Jonah was confined to the whale's belly, Christ was in the tomb.
On the day of the preparation, then, at the third hour, He received the sentence from Pilate, the Father permitting that to happen; at the sixth hour He was crucified; at the ninth hour He gave up the ghost; and before sunset He was buried.794 During the Sabbath He continued under the earth in the tomb in which Joseph of Arimathæa had laid Him. At the dawning of the Lord’s day He arose from the dead, according to what was spoken by Himself, “As Jonah was three days and three nights in the whale’s belly, so shall the Son of man also be three days and three nights in the heart of the earth.”795 The day of the preparation, then, comprises the passion; the Sabbath embraces the burial; the Lord’s Day contains the resurrection. Epistle to the Traillians
At the same time, there is the sense that while Jonah was alive in the belly, so too was Christ in the 'heart of the earth' (identified as the tomb), preaching to the dead.
God is God of the living and dead (Lk 22:38). So, while Jonah may have been alive the whole of 3 days and 3 nights, so too was Christ.
To those who believe Jonah was alive, how did Jesus do the sign of Jonah if Jesus was dead for three days and nights, but Jonah was alive?
The distinction is likely immaterial because as the Lord Himself says in Matthew 12:40, the similitude is drawn between Jonah's being in the belly of the fish and the Son of God being in the heart of the Earth for the same period of time, not necessarily between literal death and literal death.
In Jonah's prayer in Jonah chapter 2, he likens the fish's belly to "hell":
Then Jonah prayed unto the Lord his God out of the fish’s belly, And said, I cried by reason of mine affliction unto the Lord, and he heard me; out of the belly of hell cried I, and thou heardest my voice. For thou hadst cast me into the deep, in the midst of the seas; and the floods compassed me about: all thy billows and thy waves passed over me. Then I said, I am cast out of thy sight; yet I will look again toward thy holy temple. The waters compassed me about, even to the soul: the depth closed me round about, the weeds were wrapped about my head. I went down to the bottoms of the mountains; the earth with her bars was about me for ever: yet hast thou brought up my life from corruption, O Lord my God. When my soul fainted within me I remembered the Lord: and my prayer came in unto thee, into thine holy temple.
The Hebrew word translated into English as "hell" in verse 2 is Sheol, understood symbolically as the world of the dead. Therefore the similitude is complete as to its symbolism and how the Savior fulfilled or administered this sign by His being in the "heart of the Earth" and in the literal world of the dead, whereas with Jonah the "corruption" of the fish's belly was likened symbolically to the world of the dead.
Another possible symbolic connection is Jonah's use of the word "temple" in the above passage.
Then answered the Jews and said unto him, What sign shewest thou unto us, seeing that thou doest these things? Jesus answered and said unto them, Destroy this temple, and in three days I will raise it up. Then said the Jews, Forty and six years was this temple in building, and wilt thou rear it up in three days? But he spake of the temple of his body. (John 2:18-22)
This suggests that Jonah's plea for and anticipation of deliverance from the belly of the sea creature, and His "looking toward" the Lord's Holy Temple was a prefiguration of the resurrection of Christ in the temple of His body. The Lord also refers to this similitude as a sign.
