There's a common objection to the Catholic teaching on baptism that goes something like this: "You don't need to be baptized. The good thief on the cross wasn't baptized, and Jesus told him he'd be in paradise."
This is a familiar Protestant argument, but I would say it's mostly incorrect.
There is a small truth in it. Catholics do believe it's possible to be saved without water baptism — but not in the way some of our Protestant brothers and sisters think. The good thief was saved because he showed real remorse, real repentance, and real faith in Jesus. He asked for mercy, and Jesus granted it. And practically speaking, he couldn't exactly climb down from the cross to be baptized.
Jesus can make exceptions when He chooses. But when He gives us a rule and tells us to follow it, then we should follow it. If someone truly cannot receive baptism and turns to God with sincere desire, the Church teaches that God can supply the grace. This is what we call baptism of desire — the idea that a person can receive the grace of baptism without the physical sacrament if they sincerely desire it or would have desired it had they known its necessity.
The problem is that many Protestants take the exception and try to make it the rule. Since Jesus made an exception for the good thief, they want to live by the exception alone. They ignore the many verses that command baptism and cling to the one verse that shows an extraordinary circumstance. But Jesus didn't teach us to ignore His commands just because He made a rare exception.
Look at Matthew 28:19. Jesus tells the Apostles: "Go, therefore, and make disciples of all nations, baptizing them…" This is only about forty days after the crucifixion. If Jesus intended the good thief to prove that baptism wasn't necessary, why would He immediately command the Apostles to baptize the whole world?
Then there's 1 Peter 3:21, where Peter says plainly: "Baptism… now saves you."
And in John 3, when Nicodemus asks Jesus what is required for salvation, Jesus tells him he must be born again of water and Spirit. Many people focus only on the "born again" part and skip over the "water and Spirit," but Scripture consistently uses that phrase to refer to baptism.
We can even go back to Matthew 3:13–17, where Jesus Himself is baptized by John. Jesus didn't need baptism for His own sake, but He did it to "fulfill all righteousness" and to set the pattern for us. If baptism weren't part of the salvation plan, why would Jesus undergo it at all?
The bigger question is: why ignore all the baptism passages? Baptism is everywhere in the New Testament. Yes, there is one exceptional case — the good thief. But it's dangerous to build your entire theology on an exception. It's bold to expect God to give you the exception when He has already given you the normal process to follow.
There are many verses in the New Testament that call for baptism — some symbolic, some very direct. I list several below for consideration.
In the end, there is a normal process, and there are rare exceptions. When the normal process is available to us — and Jesus Himself commanded it — choosing to reject it and rely on the exception instead is not supported by Scripture.
John 1:33 — I did not know him, but the one who sent me to baptize with water told me, "On whomever you see the Spirit come down and remain, he is the one who will baptize with the Holy Spirit."
John 3:23 — John was also baptizing in Aenon near Salim, because there was an abundance of water there, and people came to be baptized.
John 4:1–2 — Jesus was making and baptizing more disciples than John (although Jesus himself was not baptizing, just his disciples).
Mark 1:4–5 — John the Baptist appeared in the desert proclaiming a baptism of repentance for the forgiveness of sins…
Mark 16:15–16 — "Whoever believes and is baptized will be saved…"
Luke 3:3 — He went throughout the whole region of the Jordan, proclaiming a baptism of repentance…
Luke 3:16 — "I am baptizing you with water, but one mightier than I is coming…"
Acts 1:5 — "John baptized with water, but in a few days you will be baptized with the Holy Spirit."
Acts 2:38 — "Repent and be baptized, every one of you…"
Acts 2:41 — Those who accepted his message were baptized…
Acts 8:12 — Men and women alike were baptized.
Acts 8:36–39 — "Look, there is water. What is to prevent my being baptized?"
Acts 9:18 — He got up and was baptized.
Acts 10:47–48 — "Can anyone withhold the water for baptizing these people…?"
Acts 16:14–15 — Lydia and her household were baptized.
Acts 16:33 — He and all his family were baptized at once.
Acts 18:8 — Many of the Corinthians believed and were baptized.
Acts 19:2–5 — They were baptized in the name of the Lord Jesus.
Acts 22:16 — "Get up and have yourself baptized…"
Romans 6:3–4 — We were buried with him through baptism into death…
Galatians 3:27 — All of you who were baptized into Christ have clothed yourselves with Christ.
1 Corinthians 1:16 — Paul baptized the household of Stephanas.
1 Corinthians 10:1–2 — All were baptized into Moses in the cloud and in the sea.
1 Corinthians 12:13 — In one Spirit we were all baptized into one body.
Titus 3:5 — He saved us through the bath of rebirth and renewal by the Holy Spirit.
Colossians 2:11–12 — You were buried with him in baptism…
Ephesians 4:4–5 — One Lord, one faith, one baptism.
Ephesians 5:26 — Cleansing her by the bath of water with the word.