Some Christian denominations outside mainstream Protestantism, such as Oneness Pentecostals, argue that the trinitarian formula doesn’t match with what the Bible has to say about baptism. They claim that baptism should be administered only “in the name of Jesus.”
For support, they appeal to passages like Acts 2:38, where Peter says, “Repent, and be baptized every one of you in the name of Jesus Christ for the forgiveness of your sins; and you shall receive the gift of the Holy Spirit.” Other passages include Acts 8:14-16 (with reference to those in Samaria who had received the word of God), 10:48 (with reference to Cornelius and his Gentile friends), and 19:5 (with reference to believers in Ephesus). Passages like these give rise to a legitimate question: why is the Church saying that we can baptize with the trinitarian formula when all the baptisms in the Bible are seemingly done “in the name of Jesus”?
The first thing that we can say in response is that the trinitarian formula can’t be rejected outright because Jesus expressly commanded the apostles to baptize using that formula: “Go therefore and make disciples of all nations, baptizing them in the name of the Father and of the Son and of the Holy Spirit” (Matt. 28:19).
A second response is that Jesus’ instruction to use the trinitarian formula is distinct in nature from the “in the name of Jesus” passages found in the book of Acts. In Matthew 28:19, Jesus is addressing ministers whom he is sending to perform baptisms. It stands to reason, therefore, that Jesus would give them the exact formula to use in administering the sacrament.
This instruction stands in contrast with the “in the name of Jesus” passages found in the book of Acts. Take Peter’s injunction in Acts 2, for example, which takes place in a public setting and is given not to those who would be performing baptisms, but to those who would receive it. Those present who were listening to his preaching were “cut to the heart” and asked him, “Brethren, what shall we do?” We shouldn’t view Peter’s response as a precise set of instructions in how baptisms are to be performed, but as an answer to their question of how to be saved—“repent and get baptized!”
Concerning Peter’s command in Acts 10:48 for Cornelius to be baptized “in the name of Jesus Christ,” here too Peter is speaking to those who will be receiving baptism, not those who would administer it. Moreover, Luke is not recording what Peter said verbatim. He merely narrates in summary form: “And he [Peter] commanded them to be baptized in the name of Jesus Christ.” It doesn’t seem that Luke intends to say that the words “in the name of Jesus” were the actual words used in administering baptism.
The other “in the name of Jesus” passages (Acts 8:14-16; 19:5) are even further removed from instructions on how to baptize. Neither are they a retelling of the exact words used for baptism, but merely passing references to the fact that some were baptized: “They had only been baptized in the name of the Lord Jesus” (Acts 8:14-16), “they were baptized in the name of the Lord Jesus” (Acts 19:5).
A third response is that we have evidence that the early Christians did in fact use the trinitarian formula. Consider, for example, Acts 19:1-5. Luke tells us that Paul passed through the upper country of Ephesus and found some believers there. Paul asked them, “Did you receive the Holy Spirit when you believed?” The believers responded, “No, we have never even heard that there is a Holy Spirit.” Puzzled as to why they never heard of the Holy Spirit, Paul asked, “Into what then were you baptized?” They responded, “Into John’s baptism.”
The implication here is that these believers in Ephesus should have heard of the Holy Spirit if they were baptized with the right baptism. If the formula were Jesus’ name only, then Paul’s question would make no sense. The question makes sense only if the name of the Holy Spirit was expected to be used in the ritual when believers were baptized, as it is in the trinitarian formula that Christ commands the apostles to use in Matthew 28:19.
The earliest record outside the Bible for the use of the trinitarian formula is the Didache, which is an early Christian handbook dating to around A.D. 50-70. It gives the following instructions on how to baptize:
And concerning baptism, thus baptize ye: Having first said all these things, baptize into the name of the Father, and of the Son, and of the Holy Spirit, in living water. But if thou have not living water, baptize into other water; and if thou canst not in cold, in warm. But if thou have not either, pour out water thrice upon the head into the name of Father and Son and Holy Spirit (7).
Given this evidence for the trinitarian formula, why all the talk about “in the name of Jesus”? It’s likely that the early Church used this expression to distinguish Jesus’ baptism from other types. Christian baptism wasn’t the only baptism in town, since John the Baptist was administering his baptism of repentance (see also Matt. 3:13-14, 21:25; Acts 1:22, 10:37). Even the Jewish ceremonial washings were considered as a baptism of sorts. For example, in Luke 11:37-38 the Pharisees invite Jesus to dine with him, and Luke tells us that the Pharisees were “astonished to see that he [Jesus] did not first wash before dinner.” The Greek word for “wash” here is ebaptizthē, the root of which is baptizō. Other traditions involve the “washing” (Greek, baptismous) of cups and vessels (Mark 7:4).
So there would have been a need to distinguish Jesus’ baptism—baptism “in the name of Jesus”—from all these other kinds of baptisms. We see this play out in Acts 19, where, after Paul realizes the believers in Ephesus were baptized only into John’s baptism, we’re told that “they were baptized in the name of the Lord Jesus” (v.5), signifying that they were baptized in the Christian way.
We find something similar in the Didache, which, after giving the trinitarian formula for baptism, refers back to it later as baptism “in the name of the Lord” (9.5). So, for the early Christians, baptism “in the name of the Lord” or “in the name of Jesus” meant baptism using the words “in the name of the Father, and of the Son, and of the Holy Spirit.”