Response: Dying is dying, suffering still occurs, the suffering is part of the death and is the sacrifice. How long someone is dead is irrelevant, since every gets resurrected and since you will be without a body in the meantime, what is it to you that you dead? Did the "10 Holy Martyrs" of Israel not actually atone for sin, since they will all be resurrected at the end of time?
The prophet tells us that this sin was unforgivable and was viewed with greater severity than every cardinal offense. With this statement the prophet alludes to the fact that the greatest scholars of Israel, the ten holy martyrs would be brutally murdered in atonement for this sin. Hashem said that the sale of Yoseif, unlike all other sins, could never be overlooked and that one day the greatest Tannaim (Mishnaic authors) would suffer inhuman torture and be taken from us in atonement for this sin. -vayeishev