Why do Christians get baptized?
The short answer is that beliefs regarding baptism vary between those claiming to be Christians and therefore the answer you get will vary.
This hasn’t always been the case, but it has become so in recent centuries.
The most common reason for "Christian" baptism today is for the baptized individual to make a public profession of their commitment to follow Jesus.
These people typically believe that they were saved (i.e., forgiven of their sins) when they confessed their sins to GOD and asked Jesus into their heart to be their Savior.
But this popular practice embraces only part of what the New Testament teaches while ignoring, misunderstanding or misapplying other Scriptures. You will not find this reason for baptism among the earliest Christians.
The earliest Christians unanimously believed, practiced and taught that baptism—complete immersion in water—was the moment at which, by faith, the cleansing blood of Jesus washed away the sins of the believer.
Jesus commanded water baptism for all His would-be disciples (see Matt. 28:16-20; Mark 16:15-16).
The book of Acts consistently shows water baptism accompanying conversions of the earliest Christians.
The apostle Paul plainly taught that water baptism is the process by which the believer dies with Jesus—the (physical) body ruled by sin is placed into the watery grave just as Jesus' body was lowered into the tomb—and the new creature (who has been freed from sin) arises from the water, just as Jesus arose from the grave (see Rom. 6:1-14).
There are other common (non-biblical) reasons why people who claim to be Christians practice baptism, including the dedication of babies to GOD (a.k.a. Christening, which isn't full immersion, but sprinkling or pouring) or joining a specific church.
Paul stated in Eph. 4:4-6 that in pure apostolic Christianity there is "one baptism" and that baptism is water immersion for the purpose of having one's sins washed clean by the blood of Jesus.
If you want to learn more about biblical baptism, download my free in-depth Biblical Baptism series.