Dr. David K. Bernard (Oneness scholar) once debated a Trinitarian that actually held that the “name” in 4:12 is possibly “God” or something not known to him. I have heard this response on several occasions as well. Most competent scholars, Trinitarian or no, should concede that the “name” of 4:12 is the name of Jesus.
In the following we shall examine the immediate context of this verse to come to a logical conclusion. We shall use the New King James Version for our text.
The Reason: Acts 4:1-6
Now as they spoke to the people, the priests, the captain of the temple, and the Sadducees came upon them, (2) being greatly disturbed that they taught the people and preached in Jesus the resurrection from the dead. (3) And they laid hands on them, and put them in custody until the next day, for it was already evening. (4) However, many of those who heard the word believed; and the number of the men came to be about five thousand. (5) And it came to pass, on the next day, that their rulers, elders, and scribes, (6) as well as Annas the high priest, Caiaphas, John, and Alexander, and as many as were of the family of the high priest, were gathered together at Jerusalem.
Peter and John have been experiencing the power of the Holy Spirit at work in their lives. Just prior to chapter four a lame man had been healed at the gate called Beautiful (3:1-10). Verse one picks up where Peter and John had been and were preaching on Solomon’s Portico (see 3:11-26), to “the people”, about the resurrected Christ. As this happened “the priests, the captain of the temple, and the Sadducees” came to them to silence their teachings about the resurrection of Jesus Christ.
The Pharisees commonly taught a resurrection possibility. The Apostolic teaching that Jesus had risen from the dead proved and guaranteed that the dead will rise to life. This teaching opposed the orthodox teachings of the Sadducee's. This guarantee of resurrection, as opposed to simply teaching the future hope of the resurrection (Pharisees), threatened the Sadducees’ security as leaders of the people.
In 4:2 the NKJV says, “they taught the people and preached in Jesus the resurrection from the dead”. The construction and flow of the text here is strange. The NKJV is a literal translation and sometimes wooden without further study. The NLT renders the same verse more clearly:
They were very disturbed that Peter and John were claiming, on the authority of Jesus, that there is a resurrection of the dead.
Basically, however, Luke means to tell us that Peter and John were using the case (‘in’, i.e. in the person, or in the case of Jesus.) of Jesus’ resurrection to prove that others would be raised from the dead as well. Therefore, we see, initially even, that the context begins with the work, power, and name of Jesus Christ. It is in and by Jesus, in name and work that the Christian faith rises or falls.
BY WHAT NAME? Acts 4:7-11
(7) And when they had set them in the midst, they asked, By what power or by what name have you done this? (8) Then Peter, filled with the Holy Spirit, said to them, Rulers of the people and elders of Israel: (9) If we this day are judged for a good deed done to a helpless man, by what means he has been made well, (10) let it be known to you all, and to all the people of Israel, that by the name of Jesus Christ of Nazareth, whom you crucified, whom God raised from the dead, by Him this man stands here before you whole. (11)This is the stone which was rejected by you builders, which has become the chief cornerstone."
When Peter and John had been arrested by the Sadducees and Company they were detained and kept for later questioning. “The Jewish high court, the Sanhedrin, had jurisdiction over matters of temple violation. It met regularly each day, with the exception of Sabbaths and feast days. Since it was now already evening and the Sanhedrin had already recessed, Peter and John would have to be detained until the court reconvened in the morning.”
The first and most important question, which sets the tenor of the most of this chapter is, “By what power or by what name have you done this?” The disciples did not act in the titles of a triune deity nor did they operate on their own accord. They were acting out as messengers of the Gospel by the power and commissioning of the name of Jesus Christ (c.f. Matthew 28:19). It was very customary for emissaries to come in the name of a King or a ruler. This was no different, the Apostles came in the name of the Lord of Lords—Jesus the Christ.
Peter responds quite boldly, “let it be known to you all, and to all the people of Israel, that by the name of Jesus Christ of Nazareth” were these miracles (lame man healed—3:1-11) done. Peter’s words were scathing and end in resurrecting the memories of the still recent death of Jesus and placing the blame upon them (vs. 10).
The actions of the Apostles, done in and by the name of Jesus, hearken to the probably extant principle that Paul would teach in Colossians 3:17
And whatever you do in word or deed, do all in the name of the Lord Jesus, giving thanks to God the Father through Him.
In verse 11 Peter utilizes a Messianic prophecy (see Psalms 118:22) against them, ironically Jesus used this quotation Himself prior to His crucifixion (see Matt. 21:42). No doubt those words still lingered in their ears. The “chief cornerstone” (vs. 11) was the highest corner-stone and was of great importance in supporting the roof. He informs them that Jesus was the stone that they had rejected. Without this support the roof would fall. This speaks of another already extant principle taught by Paul as well in 1 Corinthians 3:11
For no other foundation can anyone lay than that which is laid, which is Jesus Christ.
THE SAVING NAME:
(12) Nor is there salvation in any other, for there is no other name under heaven given among men by which we must be saved.
It is quite clear, to this point, that the context of this chapter concerns the power and name of Jesus. It was not by titles that the lame man was healed; it was by the power and invocation of Jesus name (3:6) that the lame stood up and walked. “Peter boldly asserts that the miracle has been performed in the name and power of Jesus, “whom you” crucified.” It was not because of preaching the resurrection of a triune deity that aroused the Sadducees; it was a name above every name, the name of Jesus.
Roy B. Zuck comments that, “It is necessary to respond to Jesus with belief, since there is no other name under heaven by which it is necessary to be saved.” John MacArthur says that 4:12 refers to, “the exclusivism of salvation by faith in Jesus Christ.” Zuck and MacArthur, both Trinitarians, clearly see the name of Jesus as the actual “name” in 4:12.
The 4:12 passage covers all the bases. Luke states that there is no salvation “in any other” person than Jesus and that there is no “other name” by which salvation can be extended. This clearly implies that it is on the authority of and by the name of Jesus that one is saved.
Many have mistakenly believed that the "in the name of Jesus" reference in Acts 2:38 does not denote an oral invocation. This view states that the name of Jesus was not invoked over the baptized and that it merely means "in the authority" of; therefore, a particular name is non-important and a triune title citation was probably used. The Greek-English lexicon of the New Testament and other early Christian literature (also known as the BAGD) has been the benchmark in Greek lexicons for some time. The BAGD says differently. This excerpt is from the BAGD's treatment of "name" or "onoma" (Grk. name).
γ. with ἐν: ἐν ὀνόματι of God or Jesus means in the great majority of cases with mention of the name, while naming or calling on the name (LXX; no corresponding use has been found in secular Gk.-Heitmüller p. 13ff, esp. 44; 49). In many pass. it seems to be a formula. ἐν τῷ ὀνόματι Ἰησοῦ ἐκβάλλειν δαιμόνια Mk 9:38; 16:17; Lk 9:49. τὰ δαιμόνια ὑποτάσσεται ἡμῖν ἐν τῷ ὀν. σου the demons are subject to us at the mention of your name 10:17. ποιεῖν τι ἐν τῷ ὀνόματι Ac 4:7; cf. Col 3:17. Perh. J 10:25 (but s. below). ἐν τῷ ὀν. Ἰησοῦ. . . οὗτος παρέστηκεν ὑγιής Ac 4:10. ὄν. . . ἐν ᾧ δεῖ σωθῆναι ἡμᾶς vs. 12. παραγγέλλω σοι ἐν ὀν. Ἰ. Χρ. 16:18; cf. 2 Th 3:6; IPol 5:1. σοὶ λέγω ἐν τῷ ὀν. τοῦ κυρίου Ac 14:10 D. Peter, in performing a healing, says ἐν τῷ ὀν. Ἰησοῦ Χρ. περιπάτει 3:6 (s. Heitmüller 60). The elders are to anoint the sick w. oil ἐν τῷ ὀν. τοῦ κυρίου while calling on the name of the Lord Js 5:14.—Of the prophets λαλεῖν ἐν τῷ ὀν. κυρίου 5:10. παρρησιάζεσθαι ἐν τῷ ὀν. Ἰησοῦ speak out boldly in proclaiming the name of Jesus Ac 9:27f. βαπτίζεσθαι ἐν τῷ ὀν. Ἰ. Χ. be baptized or have oneself baptized while naming the name of Jesus Christ Ac 2:38 v.l.; 10:48. αἰτεῖν τὸν πατέρα ἐν τῷ ὀν. μου (=Ἰησοῦ) ask the Father, using my name J 15:16; cf. 14:13, 14; 16:24, 26. W. the latter pass. belongs vs. 23 (ὁ πατὴρ) δώσει ὑμῖν ἐν τῷ ὀν. μου (the Father) will give you, when you mention my name. τὸ πνεῦμα ὃ πέμψει ὁ πατὴρ ἐν τῷ ὀν. μου the Spirit, whom the Father will send when my name is used 14:26. To thank God ἐν ὀν. Ἰησοῦ Χρ. while naming the name of Jesus Christ Eph 5:20. ἵνα ἐν τῷ ὀν. Ἰησοῦ πᾶν γόνυ κάμψῃ that when the name of Jesus is mentioned every knee should bow Phil 2:10. χαίρετε, υἱοί, ἐν ὀν κυρίου greetings, my sons, as we call on the Lord’s name B 1:1. ὁ ἐρχόμενος ἐν ὀν. κυρίου whoever comes, naming the Lord’s name (in order thereby to show that he is a Christian) D 12:1. ἀσπάζεσθαι ἐν ὀν. Ἰ. Χρ. greet, while naming the name of J. Chr. w. acc. of the pers. or thing greeted IRo inscr.; ISm 12:2. Receive fellow church members ἐν ὀν. θεοῦ IEph 1:3. συναχθῆναι ἐν τῷ ὀν. τοῦ κυρίου Ἰ. meet and call on the name of the Lord Jesus=as a Christian church 1 Cor 5:4. μόνον ἐν τῷ ὀν. Ἰ. Χρ. only (it is to be) while calling on the name of J. Chr. ISm 4:2.—Not far removed fr. these are the places where we render ἐν τῷ ὀν. with through or by the name (s. ἐν III 1a); the effect brought about by the name is caused by the utterance of the name ἀπελούσασθε, ἡγιάσθητε, ἐδικαιώθητε ἐν τῷ ὀν. τοῦ κυρίου Ἰ. Χρ. 1 Cor 6:11. 
One objection to the soteriological significance of this verse or at least to Jesus name baptism has been on whether or not the “salvation” in vs. 12 is truly salvation for glorification or a healing or deliverance. The Greek word for “salvation” here can be translated as “healing” or “deliverance” but neither of which is possible, as is salvation, apart from the name of Jesus.
The Messianic import of the context can be a deciding factor. The word “salvation” here goes back to Psalm 118:22 which Jesus and Peter had cited. The prominent theme of Psalm 118:22 was salvation. Verses 22-29 in Psalm 118 expect millennial deliverance. It should be certain then that in 4:12 Peter was speaking not only of individual salvation, but also holistically of the national salvation of Israel, as predicted in Psalm 118 and Malachi 4:2. In fact, this is the point of the Sanhedrin outrage (4:17). Peter is essentially telling them that they had rejected the only Savior of Israel. Thus no other way of salvation is available to people (see John 14:6; 1 Tim. 2:5). The import of the word “salvation” then should logically extend well beyond healing or deliverance from a sickness, it extends to the point of soteriological significance.
The statement that there is no salvation “in any other” reveals to us the theology of the early church. In an era of religious pluralism and the denial of the importance of the baptismal invocation of the name of Jesus, this verse stands in clear opposition.
(17) But so that it spreads no further among the people, let us severely threaten them, that from now on they speak to no man in this name. (18) So they called them and commanded them not to speak at all nor teach in the name of Jesus.
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