"Assuredly, I say to you, today you will be with Me in Paradise" (Luke 23:43). Although Jesus had silently observed the ridicule and taunting of the rulers and multitude, He is more than willing to make reply to this penitent, dying man and give him the mercy he seeks. The word "Paradise" (i.e., an enclosed park or pleasure-ground) is used in the New Testament to refer to the intermediate state of the dead (i.e., "Abraham's bosom" in Hades). The term is also used to refer to heaven itself (e.g., Rev. 2:7). This verse teaches that Jesus went to Paradise at death, and Acts 2:29-36 teaches that He went to Hades. There is no contradiction if one understands Hades to be a general term meaning the spiritual realm of the dead (i.e., departed spirits). Hades appears to have a "good" compartment and a "bad" one (e.g., Luke 16:19-31). The "good" side is known as "Paradise" or "Abraham's bosom," which apparently is where Jesus' spirit went at death (along with the spirit of the penitent thief). This thief did not go to heaven at death, but neither did Jesus (cf. John 20:17). Their bodies were buried and their spirits went to the blessed side of the Hadean realm where they would await the resurrection (which was only three brief days for Jesus).
It is tragic that so much has been made of the method of the thief's salvation in the denominational world. In their efforts to undermine the truth of the gospel plan of salvation (specifically regarding the necessity of baptism today), they fail to recognize important Biblical truths regarding this thief and his condition. The thief on the cross lived under the Old Testament dispensation of time. The last will and testament of the Lord (i.e., the New Testament) did not become effective until the death of its testator (cf. Heb. 9:15-17). Therefore, the thief on the cross is not an illustration or example of salvation for modern-day man. The New Testament was not operative when this promise of Jesus was given to the thief. The Great Commission had not even been given yet (cf. Matt. 28:19,20), and so it is ridiculous to point to the thief as one who was saved without being baptized and attempt to conclude that one can be saved in like manner today (incidentally, no one knows whether the thief was baptized or not at some point prior to his crucifixion, cf. Matt. 3:5,6). Today, for one to be saved from sin, he must be obedient to Mark 16:16, Acts 2:38, etc. One must submit to the conditions of the gospel and become a baptized, penitent believer. The thief on the cross is not an example or pattern for modern-day man regarding how to be saved any more than Noah, Abraham, or Moses are. On the Day of Pentecost in Acts 2, Peter urged his listeners--after they believed--to repent and be baptized for the remission of their sins. Thus, it is foolish for one to ignore Acts 2 (and all the other examples of conversion in the book of Acts) and go back to the thief on the cross as a "pattern" of salvation for men today. After the death of Christ, there is no evidence that anyone was saved merely by talking with Jesus.