Charles Spurgeon Commentary 1 Corinthians 15:15-17

"Yea, we are found false witnesses of God; because we witnessed of God that he raised up Christ: whom he raised not up, if so be that the dead are not raised. For if the dead are not raised, neither hath Christ been raised: and if Christ hath not been raised, your faith is vain; ye are yet in your sins." — 1 Corinthians 15:15-17 (ASV)

Yes, and we are found false witnesses of God; because we have testified of God that he raised up Christ: whom he did not raise up, if the dead do not rise. For if the dead do not rise, then Christ is not raised: and if Christ has not been raised, your faith is vain; you are still in your sins.

If Jesus Christ is not risen, he has done nothing for you; you are not saved, you are not pardoned, you are not renewed. It is all a myth, all a piece of deceit. If that fact is given up, that Christ rose from the dead, everything connected with salvation is also given up.

Yea, and we are found false witnesses of God; because we have testified of God that he raised up Christ: whom he raised not up, if so be that the dead rise not. For if the dead rise not, then is not Christ raised: and if Christ be not raised, your faith is vain; ye are yet in your sins.

So that you cannot be a Christian if you deny the resurrection of Christ.

You must give up Christianity altogether, and confess that your faith in it was a delusion, unless you believe that Jesus Christ rose from the dead, and that therefore there is a resurrection from the dead for the sons of men. Let it ever be most clearly understood that what Christ is, that his people are. There is an unbroken union between the Head and the members, so that, if he lives, they live; and if he lives not, then they live not; and if they live not, then he lives not. Jesus and those for whom he died are so intimately joined together that they are really and truly one, and nothing can ever separate them.