The necessity of baptism for salvation is a longstanding and widely accepted doctrine within most of Christianity. However, some argue that exceptions found in the Bible, such as the thief on the cross, invalidate this requirement. This argument is extremely ahistorical and commits a fallacy known as the argument by exception.
Before getting into logical arguments, I should remind you that the idea that baptism regenerates and is necessary for entering heaven is unanimously believed in the early Church. This can be demonstrated by two Protestant scholars who both recognize this fact. For instance, in his book on early Christian doctrines, JND Kelly says that baptism was always seen as a way of remitting sins, not just a symbol of faith (pp. 193-194). Protestant William Webster in his anti-Catholic history book likewise notes that the doctrine of baptism as taught by the Catholicism is universal among the Fathers. Therefore, when Protestants who deny baptismal regeneration try arguing that sola scriptura is not anti-tradition, this is not something that can be demonstrated honestly.
In any case, some Protestants who deny baptismal regeneration will argue against it using exceptions in the Bible. Baptist pastor Mike Winger makes this argument in a video about Catholicism:
[In Catholicism,] baptism is one of the many steps that you need to take in order to be saved. Now, against this, the Bible actually has examples of unbaptized saved people even after the gospel was being proclaimed.
No Christian argues that baptism is absolutely necessary for salvation—that is, needed for everyone, without exceptions. Granted, this is plainly contradicted by people in the Bible who went to heaven without water baptism. However, we would argue that baptism is conditionally necessary: generally necessary for most, but for people in extreme circumstances (such as those who physically cannot be water baptized), we have exceptions. God normally communicates grace through sacraments, but God is not bound by his sacraments.
Back to the argument by exception. This fallacy occurs when someone cites an exception to attempt to invalidate a general rule. Here is an example:
“The law states that it is illegal to exceed the posted speed limit on public roads. However, there are occasions when ambulances exceed the speed limit to reach an emergency situation more quickly. Since ambulances are allowed to break the speed limit rule in certain exceptions, this proves that the law prohibiting exceeding the speed limit is invalid and does not actually need to be followed.”
This is not a valid logical structure. Just because speeding is allowed in extreme circumstances, that does not mean that everyone can speed all the time. Someone who argues that baptism cannot be necessary for salvation because of exceptions in the Bible is committing a similar fallacious argument.
This fallacious argument can also be demonstrated by using another, more relevant example. Many Protestants who deny baptismal regeneration would also argue that someone who does not believe in Jesus could be saved in extreme circumstances. We could imagine a nine-year-old who dies, and all she ever knew was atheism because both of her parents were atheists. Since this individual was quite young and would not have known anything besides atheism, she could be saved, even though she did not believe that Jesus is God.
However, what if someone then says, “See? You don’t need to believe in Jesus to go to heaven! We have an exception right here. Christians are wrong when they argue that one must believe in Jesus in order to go to heaven.”
Most Christians would not believe that this is a valid line of logic. Just because there are exceptions, this does not invalidate the general rule that has been accepted universally by the Fathers.
I should also add this—if baptism is universally accepted as way of regenerating God’s people, it must also be the case that eternal security is unanimously rejected. After all, since baptism saves, and not everyone who is baptized stays a Christian for his entire life, it must be so that the Fathers also believed that a genuinely saved Christian could lose his salvation. Therefore, Protestants who argue that Christians cannot lose their salvation while also trying to argue that sola scriptura is not anti-tradition are likewise not being consistent.
In summary, using exceptions found in the Bible, such as the thief on the cross, to argue against the necessity of baptism for salvation is an example of the argument by exception fallacy. This faulty reasoning attempts to invalidate a widely accepted general principle by citing isolated exceptions. However, as demonstrated through examples like speeding laws, the existence of rare exceptions does not negate an established rule or requirement.
The doctrine of baptismal regeneration and the necessity of baptism was unanimously upheld by the early Church Fathers. Trying to use exceptional cases to undermine this longstanding belief commits a logical fallacy and fails to provide a valid counterargument.