Well, you offered no scriptural proof concerning the thief so I'll just move on from that.
A few remarks:
1. Christian baptism presumes sincere faith (
Acts 8:36-37). So when we speak of baptism, we do not speak of some sham, nor infant "baptism", nor forced "baptisms", so called. Instead, we are speaking of a sincere believing response to the Gospel.
2. Repentance means a reversal of one's course. It means ceasing to be whatever you were and becoming a Christian. Or in the case of backsliders, ceasing to be a disobedient Christian and becoming an obedient Christian. Biblical repentance for sinners includes becoming a Christian, a disciple of Christ. One does not become a Christian apart from baptism into the name of Christ.
3. Many are non-apostolic, but instead are modern Protestant, baptistic, evangelical in regards to their doctrine of conversion. This modern heretical and unbiblical view holds "repentance" to be a specific moment in time in which a "decision" is made to "accept Jesus as Saviour" or to ask for forgiveness from God or to "begin following Christ" or some other variation on the same theme. It is almost ALWAYS identified with a prayer and a "trip to the altar". The Bible NEVER shows conversion in this manner.
This modern decisionism was practically invented by Charles Finney and quickly adopted by Methodists, some New Light Presbyterians, other "holiness" and "revival" movements, in the early 1800s. He taught that God uses "means" (tools, methods) in converting and saving sinners, especially during revivals. Revival preachers must use certain means or methods to bring the Gospel to sinners and see their conversion. One of these means which he invented was the "Anxious Seat". This method involved preaching a revival message, then inviting anyone who was "anxious about the condition of their soul" to come sit up front so the preacher and a few other saints or family members could pray for the person and plead with them to submit to Christ. This was adopted by Methodists who would set up a "Penitent Form" or "Mourner's Bench", a makeshift bench where those under conviction could come and pray to God for forgiveness while the preacher and saints prayed for them and exhorted them to put total faith in Christ to absolve them of their sins and sanctify them by removing the "root of sin and rebellion from their heart".
Later, Dwight Moody modified it and popularised it as "coming forward" and "accepting Jesus as your personal Saviour". Many modern Oneness Pentecostals have taken this same methodology and they call it "repentance", where people who want to be saved "come forward" to "the altar" (modern version of the Mourner's Bench) to pray to God for forgiveness and "make a decision for Christ".
What's funny is Finney, the inventor of the whole thing, admits in his sermon on Means To Be Used In Revivals that the Anxious Seat and the Mourner's Bench are modern methods that
in Bible days was served by baptism. Meaning that what you all today call "repentance" as an act taking place in a meeting is a
modern substitute for baptism.
4. Baptism is the God-ordained means by which a person is placed into Christ, identifying with His substitutionary death and atonement (
Romans 6:3-7), it is the means by which Christ saves us (
1 Peter 3:21). Since apart from the blood there is no release from sins (
Hebrews 9:22), and since the blood of Christ is a reference to His death for our sins (
1 Corinthians 15:3,
Revelation 1:5), then
baptism is the event in which Christ's death is applied to us as an effective covering or atonement for sins, securing the release (remission or forgiveness) of our sins and debt we thereby had incurred.
5. Every decision has two parts. First, the intention, followed by the actual deciding to do something which happens when the intention is acted upon. If you decide to go to the store, but never leave the house, did you really DECIDE TO GO to the store? If you decide to become a Christian, you need to then actually become a Christian. The mere mental decision to do something is not the person actually choosing a course of action, one must actually DO the thing decided upon. Becoming a Christian is done by being baptized into Christ's Name, making a public confession of Christ before others. If you "decide" to get baptized, have you thereby been baptized? No, you must actually DO it. If you "decide" to turn from sin and follow Christ and be His disciple, have you thereby done it? No, must actually DO it, you must actually cease from sinning and actually become His disciple by being baptized in His Name:
James 2:19-26 KJV
Thou believest that there is one God; thou doest well: the devils also believe, and tremble. [20] But wilt thou know, O vain man, that faith without works is dead? [21] Was not Abraham our father justified by works, when he had offered Isaac his son upon the altar? [22] Seest thou how faith wrought with his works, and by works was faith made perfect? [23] And the scripture was fulfilled which saith, Abraham believed God, and it was imputed unto him for righteousness: and he was called the Friend of God. [24] Ye see then how that by works a man is justified, and not by faith only. [25] Likewise also was not Rahab the harlot justified by works, when she had received the messengers, and had sent them out another way? [26] For as the body without the spirit is dead, so faith without works is dead also.
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