Baptism is one of two ordnances given by Christ to the Disciples that they should follow. The other being communion. Baptism just like communion has taken on many forms and exactly how baptism is performed and when it is performed varies by culture, tradition, and denomination.
The word baptism is not exactly a transliteration of the Greek but it is close. βαπτίζω (baptizo) or βάπτισμα (baptisma) are the basic forms and one can see the similarity between those and the contemporary baptized and baptism. Most likely the Greek words were carried over into an English form long before formal English translations of scripture meaning Christians were baptizing cross culturally from the very early church days and that included evangelism to the English speakers of ancient days. Transliteration typically means the translators when translating the scriptures from Greek to the English did not translate the original Greek word into a matching English word or phrase. They kept the original Greek word but converted it to the phonetic equivalent in the target alphabet. It seem likely that the now common “Baptism” or “Baptized” were already in use when the formal King James Version was created thus cementing that word in our contemporary language.
So what does Baptism mean? If they had simply translated the word what would that translation look like using the original meaning? Strong’s Dictionary provides the basic definition for baptisma as the “process of immersion, submersion and emergence” usually in regard to dipping something into water and then removing it out of the water. Strong’s Dictionary for baptizo provides the definition “to make overwhelmed (i.e. fully wet)”. Baptism as originally envisioned by the early church was a full emersion or washing of a person.
21 Baptism (baptisma), which corresponds to this, now saves you, not as a removal of dirt from the body but as an appeal to God for a good conscience, through the resurrection of Jesus Christ, 1 Peter 3:21 ESV
38 And he commanded the chariot to stop, and they both went down into the water, Philip and the eunuch, and he baptized (baptizo) him. Acts 8:38 ESV
So why not translate the above as both went down into the water, Philip and the eunuch, and Philp made the eunuch fully wet or Philip dunked the eunuch under the water? Whatever their reasons I am grateful for the God directed outcome and significance to everyone that the original word was preserved. Baptism is a significant event in the life of a believer both spiritually and physically and so it is fitting that the near original word be used to describe the event.
Baptism then as practiced by the typical evangelical protestant church is a public service either inside a church made baptistery or outdoors in a pool, lake, or river where the participant acknowledges Christ as savior and then they are bodily immersed in water. This service is intended as a public profession of faith by the participant to say that he or she has accepted Christ as their savior and that they want to follow Christ all the days of their life. Ideally this public profession is representative to what has already occurred spiritually between the individual’s spirit and the Holy Spirit.
Why Baptism and who should participate? Let me start with who should be baptized. Baptism being described in this post should only occur with children or adults who are fully aware and able to say yes this is what has happened spiritually and this is what they want to proclaim publically. Infant baptism as performed by some Christian traditions would be something different. If as a reader of this you were baptized as a child but not of a choice that you made personally then I would like for you to consider this baptism of obedience that represents what happened between you and God. In the example of Philip and the eunuch baptism was something the eunuch wanted to do. It was a response to his hearing the good news of Jesus.
32 Now the passage of the Scripture that he was reading was this: “Like a sheep he was led to the slaughter and like a lamb before its shearer is silent, so he opens not his mouth. 33 In his humiliation justice was denied him. Who can describe his generation? For his life is taken away from the earth.” 34 And the eunuch said to Philip, “About whom, I ask you, does the prophet say this, about himself or about someone else?” 35 Then Philip opened his mouth, and beginning with this Scripture he told him the good news about Jesus. 36 And as they were going along the road they came to some water, and the eunuch said, “See, here is water! What prevents me from being baptized?” Acts 8:32-36 ESV
Hearing the good news of Jesus from Philip the eunuch wanted to cement in the physical what had just occurred in his heart. Submission and obedience.
In him you also, when you heard the word of truth, the gospel of your salvation, and believed in him, were sealed with the promised Holy Spirit, Ephesians 1:13 ESV
Who should be baptized then? Those who have submitted to Jesus Christ. Do you know Him? Have you been saved? Born again into a life that follows the Spirit? If so then you are someone who should be baptized.
Finally we need to address the why question. Why should you be baptized? Baptism does not save. Only faith in Jesus Christ saves. Christianity is not a works based religion.
8 For by grace you have been saved through faith. And this is not your own doing; it is the gift of God, 9 not a result of works, so that no one may boast. Ephesians 2:8-9 ESV
Baptism does not save so why do it? Baptism is a tangible and public event that clearly proclaims to other people where the participant stands in regard to God. One could be saved in a real relational moment with God. But God does not want that private relational moment to be hidden unknown by friends and family. Paul in his letter to the Romans illustrates the point.
10 For with the heart one believes and is justified, and with the mouth one confesses and is saved. Romans 9:10 ESV
Paul is not saying that a confession saves because we are not saved by works. Paul is saying that the outflow of what happened in the heart is a public and spoken profession. “I have been saved. Christ is my Lord and Savior” it is a message that burns internally so that it has no room except for escape.
Baptism is a formal event to mark in time a date and a place where an individual publically proclaimed before friends and family that Jesus is Lord.