In Acts 10, the sequence of events are reversed from the norm: in this chapter, the Holy Ghost was poured out upon the gentiles first, then they were baptized. Unfortunately, as applied in most modern doctrine, this has led to many false conclusions about the timing and manner of salvation. Biblically speaking, however, there really is a reason for the reversal of these events, and will be discussed at more length in section 13.
Thus far, salvation has been only for the original disciples of Jesus Christ (Acts 1: Day of Pentecost, etc.), then the rest of the Jews (Acts 2), then to the Samaritans (Acts 8), and finally to an Ethiopian eunuch spoken of in Acts 8. This eunuch was either a diaspora Jew in the service of the queen of Ethiopia, or he was a proselyte (a convert) to Judaism. Finally, Paul was "saved" in Acts 9. All of these people and groups of people mentioned thus far (as of Acts 9) are circumcised. Up to this point, preaching the word of Jesus Christ to the uncircumcised was simply unthinkable! Evidence of this can be seen in a statement made by Peter:
ACTS 10:28 And he said unto them, Ye know how that it is an unlawful thing for a man that is a Jew to keep company, or come unto one of another nation; but God hath shewed me that I should not call any man common or unclean.
So even the Twelve had to be convinced of God's salvation for the gentiles by none less than God Himself.
ACTS 10:1 There was a certain man in Caesarea called Cornelius, a centurion of the band called the Italian band,
ACTS 10:2 A devout man, and one that feared God with all his house, which gave much alms to the people, and prayed to God alway.
ACTS 10:3 He saw in a vision evidently about the ninth hour of the day an angel of God coming in to him, and saying unto him, Cornelius.
ACTS 10:4 And when he looked on him, he was afraid, and said, What is it, Lord? And he said unto him, Thy prayers and thine alms are come up for a memorial before God.
ACTS 10:5 And now send men to Joppa, and call for one Simon, whose surname is Peter:
ACTS 10:6 He lodgeth with one Simon a tanner, whose house is by the sea side: he shall tell thee what thou oughtest to do.
The Greek word for "oughtest" in Acts 10:6 is the exact same Greek word as "must" in Acts 9:6:
ACTS 9:6 And he trembling and astonished said, Lord, what wilt thou have me to do? And the Lord said unto him, Arise, and go into the city, and it shall be told thee what thou must do.
Let us refer to Strongs Exhaustive Concordance, Complete and Unabridged, Compact Edition, by James H. Strong, Baker Book House, Grand Rapids, concordance pp. 702, 762, Greek lexicon p. 21.
Both the Greek word for "oughtest" (in Acts 10:6) and for "must" (in Acts 9:6) are the same Greek word. In both cases, the original word is:
1163 δει dei; 3rd person singular act pres. of 1210; also δεον deon; it is (was, etc.) necessary (as binding)
and 1210 (from which 1163 is derived) is:
1210 δεω deo; a primary verb; to bind
So in either case (Acts 9:6 or Acts 10:6), the word "must" would be the better word to use (in modern English). As in,
ACTS 9:6 And he trembling and astonished said, Lord, what wilt thou have me to do? And the Lord said unto him, Arise, and go into the city, and it shall be told thee what thou MUST do.
or, keeping closer to this particular message:
ACTS 10:5 And now send men to Joppa, and call for one Simon, whose surname is Peter:
ACTS 10:6 He lodgeth with one Simon a tanner, whose house is by the sea side: he shall tell thee what thou [MUST] to do.
After all, since 1611, when the Bible was translated into English (as the "King James Version"), English has changed somewhat.
At Acts 10:1-6 (above), the angel told Cornelius to send men to bring the Apostle Peter to him, so that he could be told what he "must" do. The entire discourse and sequence of events is recorded at Acts 10. Only the important points to this topic (baptism in water) will be listed:
ACTS 10:36 The word which God sent unto the children of Israel, preaching peace by Jesus Christ: (he is Lord of all:)
...
ACTS 10:42 And he commanded us to preach unto the people, and to testify that it is he which was ordained of God to be the Judge of quick and dead.
ACTS 10:43 To him give all the prophets witness, that through his name whosoever believeth in him shall receive remission of sins.
ACTS 10:44 ¶ While Peter yet spake these words, the Holy Ghost fell on all them which heard the word.
ACTS 10:45 And they of the circumcision which believed were astonished, as many as came with Peter, because that on the Gentiles also was poured out the gift of the Holy Ghost.
ACTS 10:46 For they heard them speak with tongues, and magnify God. Then answered Peter,
ACTS 10:47 Can any man forbid water, that these should not be baptized, which have received the Holy Ghost as well as we?
ACTS 10:48 And he COMMANDED them to be baptized in the name of the Lord. Then prayed they him to tarry certain days.
12.1.1 Gentiles (non-Jews) are required to believe, and to be baptized in water. Peter (with six others) was sent to Cornelius' house, to tell them what they "must" do (section 12.0). Peter told them that "whosoever believeth in him (Jesus) shall receive remission of sins," at Acts 10:43. In addition, Peter COMMANDED them to be baptized! This is consistant with the pattern we've seen earlier in Acts: that men must 1) believe, and 2) be baptized in the name of Jesus Christ. (cf. Acts 2:38). If you will recall, Jesus said:
MARK 16:16 He that believeth and is baptized shall be saved; but he that believeth not shall be damned.
By reviewing Acts 10:43,48, we see a word-for-word fulfillment of Christ's commandment.
12.1.2 Gentiles (non-Jews) are to be baptized "in the name of Jesus Christ." Per Acts 10:48, they were baptized "in the name of the Lord." The only Lord mentioned was "Jesus Christ":
ACTS 10:36 The word which God sent unto the children of Israel, preaching peace by Jesus Christ: (he is Lord of all:)
ACTS 10:43 To him give all the prophets witness, that through his name whosoever believeth in him shall receive remission of sins.
ACTS 10:48 And he commanded them to be baptized in the name of the Lord. Then prayed they him to tarry certain days.
The name of "Jesus Christ" is reiterated in verse 43. Cornelius, his kinsmen and near friends (Acts 10:24) were baptized, saying, in the name of "Jesus Christ!" (We have already seen in section 6 that there is no precedent whatsoever of anybody ever having been baptized, saying, "In the name of the Father, and of the Son, and of the Holy Ghost," and that that phrase is never used anywhere in the book of Acts.)
12.1.3 Baptism in the name of Jesus Christ is a commandment that must be obeyed. Even though these people were already filled with the Holy Ghost (Acts 10:44-45), the Apostle Peter nonetheless COMMANDED them to be water baptized in the name of Jesus Christ (Acts 10:48). "Jesus Christ" is the only Lord mentioned (Acts 10:36). This is a profound statement regarding the importance of water baptism! (It is imperative!)
12.1.4 Baptism is not for the purposes of "identification with," nor is it an "outward sign of an inward change." How do we know this? At Acts 10:44-45, the Holy Ghost was poured out upon these people—unmistakably "identifying" them with Jesus Christ. This was already done before they were baptized in water! In fact, this is precisely the reason why Peter commanded them to be baptized in water (Acts 10:47).
The purpose of this reversal of events (i.e., first being filled with the Holy Ghost, then being baptized in water) will be discussed at more length in section 13.
In the book of Acts thus far (chapters 1 through 10), we have seen an ever–expanding circle of inclusion of who could be saved. Salvation began with only the Jews (and Jewish proselytes)—all previously faithful to God through the Law of Moses, (cf. Luke 24:47/Acts 2:38). This circle then expanded to include the Samaritans—the descendants of Jews who intermarried with the "heathen nations" around them, but who were at least part Jewish, circumcised, and in the Land of Israel (Acts 8:5-25). Next, salvation included those faithful to God in the diaspora (i.e., outside the Land of Israel), namely, the eunuch of Acts 8:26-39. Finally, salvation was offered to everyone else (i.e., the uncircumcised nations) beginning with Cornelius!
As this circle of inclusion was extended to each of these new groups of people, the precedent of water baptism in the name of Jesus Christ is specifically written in the Holy scriptures, every time.