Did Jesus really die on the cross?

Yes, Jesus really did die on a cross. The scriptures teach this in numerous places.  Following are two of them:

• "And as they were coming out, they found a man of Cyrene named Simon, whom they pressed into service to bear His cross," (Matt. 27:32).
• "Therefore the soldiers did these things. But there were standing by the cross of Jesus His mother, and His mother’s sister, Mary the wife of Clopas, and Mary Magdalene," (John 19:25).

There is dispute on the Greek word for "cross" which is "stauros."  It can mean an upright stake or a cross.  Therefore, some groups like the Jehovah's Witnesses, say that Jesus died on a vertical stake.  But then, others simply deny that Jesus was crucified at all and they claim He died of old age or some other natural sickness. Both of these conjectures are in error according to the New Testament.

First of all, there is a verse in the New Testament that demonstrates Jesus did not die on a vertical stake without a cross bar.  If Jesus died on a vertical stake, then His hands would have been placed together over His head, one on top of another. It would be very easy to then take a single nail and drive it through both wrists at the same time. This is how crucifixion was done when victims were crucified in this manner.  However, if a person was crucified on a cross, then two nails were required, one for each wrist, since the hands would be spread apart.
If we look at  John 20:25 we see that the plural word "nails" is used in reference to Jesus' hands.

"The other disciples therefore were saying to him, "We have seen the Lord!" But he said to them, "Unless I shall see in His hands the imprint of the nails, and put my finger into the place of the nails, and put my hand into His side, I will not believe," (NASB).

The plural form "nails" is used.  This means that more than one nail was used upon Jesus' hands.  Therefore, we can conclude that the most logical explanation for the plural use of nails is that there is at least two nails, one for each hand that was stretched out from left to right as would be done if Jesus were crucified on a cross.  This would mean that the torture stake, or the vertical stake theory would be invalid.

Did Jesus really die on the cross?

According to the gospel accounts, Jesus went through six different trials before He was condemned to die on a cross. Three of the trials were before Gentiles and three were before the Jews. He was repeatedly put before people to be tried and the whole time He was under heavy guard.  They knew who Jesus was. So, this excludes the possibility of mistaken identity. Furthermore, it is highly unlikely that the Romans would have crucified a man by mistake.   Remember, Jesus had been performing many miracles and was quite well known in the area. Since the Roman soldiers had Him in their possession during the trials, during the beatings, and finally on the way to the cross, the most logical conclusion is that they did not make a mistake and crucified someone else instead of Jesus.  Therefore, we can logically conclude that Jesus really did die on a cross.