There is a resurrection of the dead: Jesus' proof by contradiction

[TonyChanYT]

Matthew 22:

23The same day Sadducees came to him, who say that there is no resurrection, and they asked him a question,

Let proposition R1 = there is resurrection.

The Sadducees do not believe in the resurrection. They believe ¬R1.

24b “Teacher, Moses said, ‘If a man dies having no children, his brother must marry the widow and raise up offspring for his brother.’ 25 Now, there were seven brothers among us. The first married and died, and having no offspring left his wife to his brother. 26 So too the second and third, down to the seventh. 27 After them all, the woman died. 28 In the resurrection, therefore, of the seven, whose wife will she be? For they all had her.”

Yet, their question assumed the resurrection.

Were the Sadducees being sarcastic?

No. In modern logic terminology, they attempted a proof by contradiction by assuming the negation or opposite of what they were trying to prove.

Assume R1.

Whose wife will she be for they all had her?

According to their logic, there was no answer to this question. Therefore, the assumption R1 is false.

End of Proof, so they thought. However, technically speaking, their proof did not supply a formal contradiction. They only supply a question that they cannot answer.

Now, it is Jesus' turn. Jesus also uses proof by contradiction (aka indirect proof):

31 as for the resurrection of the dead, have you not read what was said to you by God: 32‘I am the God of Abraham, and the God of Isaac, and the God of Jacob’? He is not God of the dead, but of the living.”

Jesus believes R1.

Using proof by contradiction. Jesus assumed ¬R1.

But then in Exodus 3:

6 And he said, “I am the God of your father, the God of Abraham, the God of Isaac, and the God of Jacob.”

The LORD is the God of Abraham.

Abraham is dead.

The LORD is the God of the dead = D1.

But in reality, Matthew 22:

32 I am the God of Abraham, the God of Isaac, and the God of Jacob’? He is not the God of the dead but of the living.”

Let proposition L1 = The LORD is the God of the living.

D1 = ¬L1.

Jesus has found a formal contradiction!

Therefore, the opposite of the assumption is true: There is a resurrection of the dead.

End of Proof.

Both the Sadducees and Jesus use the method of proof by contradiction. Because of their difference in beliefs, their initial assumptions are opposite to each other. The Sadducees failed to supply a formal contradiction to complete their proof. Jesus, on the other hand, did.

See also Paul's proof.

 

[Randy Kluth]

Yes, the Sadducees' argument assumes a contradiction. If God wants fidelity in a marriage, how can there be fidelity in a marriage involving 7 different spouses who had been married at different times? If there is a resurrection this appears to be a contradiction with respect to the law prohibiting adultery.

Jesus answers this by claiming it is a non sequitur argument, being that it assumes conditions exist after the resurrection as existed prior to the resurrection. We might assume, in defense of the Law, that once the earth is full, then the need for reproduction and for marriage is gone, and men would more resemble asexual angels than sexual mortals. That would disallow any adulterous polygamy after the resurrection.

To assume the same circumstances exist after death as before death is not proven. It would be more reasonable to assume that if there is a resurrection, conditions must be different to prevent an adulterous polygamy. God would not contradict His Moral Law.

But you're right. The Sadducees assumed the opposite could not be true, that polygamy (of the adulterous kind) could not exist after the resurrection if it was viewed as adulterous before the resurrection. A current adulterous polygamy would not allow a resurrection to the same.

But Jesus argued the opposite of conditions after the resurrection as conditions before the resurrection. The current life leads to death with promises that remain, requiring a resurrection.

Promises God made to Abraham, Isaac, and Jacob before they died required that they be resurrected in order to obtain all that has been promised them, including that which they have not yet received. And the proof that this is so is that even now those promises are being fulfilled.

Jesus provided prophetic proof in current events. The Sadducees exercised faulty logic and made unjustified assumptions that contradicted the Law.