Great question considering that the Old Testament mentions that Elijah and Enoch were carried straight up to Heaven. Before Jesus' incarnation, death and resurrection there was no access to Heaven because of the rupture of original sin. For this reason to restore us to His original intent, that we love Him and serve Him in this life and join Him in Heaven in eternal bliss, God sent His Son into the world in the form of man. He suffered, died and was buried and descended into the realm of the dead, which is best called Hades because hell can be confused with the place of punishment called the Hell of the damned. Jesus set free the just captives who were awaiting their liberation. Some postulate that in His three days in the tomb He preached to those who did not know Him so that they might come to accept Him. Many people have a notion that when we die the righteous automatically go to Heaven and are in a glorified resurrected body but this is not quite the case. Our bodies will be raised on the Last Day or when Jesus comes in Glory for the Final Judgment. The saints in Heaven are not diconnected souls without bodies but they somehow participate in a glorified body which some refer to as the Intermediate State. We must remember that the process of our going forth from this life to the next is a mystery and something that we need to respect and bow to. We can do others a great disservice by enabling the attitude that we can mistreat this body because it is only for this earth or that we don't need to do everything possible to atone for our sins now as opposed to finding out in Purgatory that we were greatly mistaken and now must suffer the consequences. Back to Elijah and Enoch, their being carried to Heaven without apparantly passing through death does not mean that they preceded Jesus but rather that they still had to wait for Him to open the gates.