A:According to the gospels, Jesus was on the cross for six hours. The sequence in Mark's gospel is as follows: "It was the third hour when they crucified him... At the sixth hour darkness came over the whole land until the ninth hour... With a loud cry, Jesus breathed his last" (Mark 15:25,33,37). Regardless of the precise amount of time that Jesus was on the cross, it is true that some men were on crosses for days on end before they finally died. In fact, when Pilate orders that the legs of the crucified be broken by the attending soldiers, he does so to expedite their deaths so that their bodies may be taken down before the Sabbath. Jesus, however, is found to be already dead (cf. John 19:31-34).
Even with Jesus' relatively quick death being duly noted, he still suffered. The scourging, the road to Golgotha with a crossbeam on his back, the nails driven through his arms, and the slow asphyxiation by which he died would have been unbearable. Indeed, we get our English word "excruciating" from "crucifixion." Such is the suffering of the cross.
Seneca, a Roman philosopher who lived at the time of Jesus, describes the horror of crucifixion thusly:
Can anyone be found who would prefer wasting away in pain dying limb by limb, or letting out his life drop by drop, rather than expiring once for all? Can any man by found willing to be fastened to the accursed tree, long sickly, already deformed, swelling with ugly wounds on shoulders and chest, and drawing the breath of life amid long drawn-out agony? He would have many excuses for dying even before mounting the cross (Dialogue 3:2.2).
It is no surprise, then, that 600 years before Jesus, the prophet Isaiah foretells that the Christ will be "a man of sorrows, and familiar with suffering" (Isaiah 53:3). Finally, regardless of how great or how small Jesus' sufferings were, they were clearly sufficient to accomplish the forgiveness of our sins. That is what matters.