Eph 4 Spriit Baptism, not Water Baptism, is Salvific
In Eph 4, the apostle is not counting baptisms, but saying that all Christians have the same baptism. The one baptism that all Christians have is Spirit baptism, not water baptism. 1 Cor 12:13 indicates that all Christians have Spirit baptism. They do not all have water baptism.
The one Must-I-Do to become a Christian is believe on the Lord Jesus Christ (Acts 16).
Occasionally a man may believe in Christ as Savior, yet die before he is baptised, as apparently was the case with the thief on the cross. All believers should report to the water to be dipped (baptised). But in fact many are never dipped, but only sprinkled (which is not what baptizo means at all).
Water baptism is clearly distinguished from Spirit baptism, which was yet future in Acts 1 (not many days hence). That makes 2 baptisms.
There is a 3rd baptism mentioned, a special baptism which Christ suffered, which appears to refer to the crucifixion. But this 3rd baptism is something that some apostles would also endure. My explanation is that when a Christian is baptised by the Spirit & put into the Body of Christ, that accomplishes so intimate a union that the believer is said to have been baptised into Christ (Rom 6) and thus co-crucified, co-raised, and seated with Christ in Him in Heaven.
Gal 2 says "I have been crucified with Christ."
I take it that when one is baptised into the Body of Christ, that unites the believer with Christ's cross-baptism. And thus I understand this scripture:
But Jesus said unto them, Ye know not what ye ask. Are ye able to drink the cup that I drink? or to be baptized with the baptism that I am baptized with? And they said unto him, We are able. And Jesus said unto them, The cup that I drink ye shall drink; and with the baptism that I am baptized withal shall ye be baptized:
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I indeed baptize you in water unto repentance: but he that cometh after me is mightier than I, whose shoes I am not worthy to bear: he shall baptize you in the Holy Spirit and in fire:
Then cometh Jesus from Galilee to the Jordan unto John, to be baptized of him. But John would have hindered him, saying, I have need to be baptized of thee, and comest thou to me?
And Jesus, when he was baptized, went up straightway from the water: and lo, the heavens were opened unto him, and he saw the Spirit of God descending as a dove, and coming upon him;
Go ye therefore, and make disciples of all the nations, baptizing them into the name of the Father and of the Son and of the Holy Spirit:
John came, who baptized in the wilderness and preached the baptism of repentance unto remission of sins. And there went out unto him all the country of Judaea, and all they of Jerusalem; and they were baptized of him in the river Jordan, confessing their sins.
I baptized you in water; but he shall baptize you in the Holy Spirit.
And it came to pass in those days, that Jesus came from Nazareth of Galilee, and was baptized of John in the Jordan.
And king Herod heard thereof; for his name had become known: and he said, John the Baptizer is risen from the dead, and therefore do these powers work in him.
And she went out, and said unto her mother, What shall I ask? And she said, The head of John the Baptizer.
But Jesus said unto them, Ye know not what ye ask. Are ye able to drink the cup that I drink? or to be baptized with the baptism that I am baptized with? And they said unto him, We are able. And Jesus said unto them, The cup that I drink ye shall drink; and with the baptism that I am baptized withal shall ye be baptized:
He that believeth and is baptized shall be saved; but he that disbelieveth shall be condemned.
He said therefore to the multitudes that went out to be baptized of him, Ye offspring of vipers, who warned you to flee from the wrath to come?
And there came also publicans to be baptized, and they said unto him, Teacher, what must we do?
John answered, saying unto them all, I indeed baptize you with water; but there cometh he that is mightier than I, the latchet of whose shoes I am not worthy to unloose: he shall baptize you in the Holy Spirit and in fire:
Now it came to pass, when all the people were baptized, that, Jesus also having been baptized, and praying, the heaven was opened,
And all the people when they heard, and the publicans, justified God, being baptized with the baptism of John. But the Pharisees and the lawyers rejected for themselves the counsel of God, being not baptized of him.
But I have a baptism to be baptized with; and how am I straitened till it be accomplished!
And they asked him, and said unto him, Why then baptizest thou, if thou art not the Christ, neither Elijah, neither the prophet? John answered them, saying, I baptize in water: in the midst of you standeth one whom ye know not,
These things were done in Bethany beyond the Jordan, where John was baptizing.
And I knew him not; but that he should be made manifest to Israel, for this cause came I baptizing in water.
And I knew him not: but he that sent me to baptize in water, he said unto me, Upon whomsoever thou shalt see the Spirit descending, and abiding upon him, the same is he that baptizeth in the Holy Spirit.
After these things came Jesus and his disciples into the land of Judea; and there he tarried with them, and baptized. And John also was baptizing in Enon near to Salim, because there was much water there: and they came, and were baptized.
When therefore the Lord knew that the Pharisees had heard that Jesus was making and baptizing more disciples than John (although Jesus himself baptized not, but his disciples),
And he went away again beyond the Jordan into the place where John was at the first baptizing; and there he abode.
for John indeed baptized with water; but ye shall be baptized in the Holy Spirit not many days hence.
And Peter said unto them, Repent ye, and be baptized every one of you in the name of Jesus Christ unto the remission of your sins; and ye shall receive the gift of the Holy Spirit.
They then that received his word were baptized: and there were added unto them in that day about three thousand souls.
But when they believed Philip preaching good tidings concerning the kingdom of God and the name of Jesus Christ, they were baptized, both men and women. And Simon also himself believed: and being baptized, he continued with Philip; and beholding signs and great miracles wrought, he was amazed.
for as yet it was fallen upon none of them: only they had been baptized into the name of the Lord Jesus.
And as they went on the way, they came unto a certain water; and the eunuch saith, Behold, here is water; what doth hinder me to be baptized? And he commanded the chariot to stand still: and they both went down into the water, both Philip and the eunuch, and he baptized him.
And straightway there fell from his eyes as it were scales, and he received his sight; and he arose and was baptized;
Can any man forbid the water, that these should not be baptized, who have received the Holy Spirit as well as we? And he commanded them to be baptized in the name of Jesus Christ. Then prayed they him to tarry certain days.
And I remembered the word of the Lord, how he said, John indeed baptized with water; but ye shall be baptized in the Holy Spirit.
And when she was baptized, and her household, she besought us, saying, If ye have judged me to be faithful to the Lord, come into my house, and abide there. And she constrained us.
And he took them the same hour of the night, and washed their stripes; and was baptized, he and all his, immediately.
And Crispus, the ruler of the synagogue, believed in the Lord with all his house; and many of the Corinthians hearing believed, and were baptized.
And he said, Into what then were ye baptized? And they said, Into John’s baptism. And Paul said, John baptized with the baptism of repentance, saying unto the people that they should believe on him that should come after him, that is, on Jesus. And when they heard this, they were baptized into the name of the Lord Jesus.
And now why tarriest thou? arise, and be baptized, and wash away thy sins, calling on his name.
Or are ye ignorant that all we who were baptized into Christ Jesus were baptized into his death?
Is Christ divided? was Paul crucified for you? or were ye baptized into the name of Paul? I thank God that I baptized none of you, save Crispus and Gaius; lest any man should say that ye were baptized into my name. And I baptized also the household of Stephanas: besides, I know not whether I baptized any other. For Christ sent me not to baptize, but to preach the gospel: not in wisdom of words, lest the cross of Christ should be made void.
and were all baptized unto Moses in the cloud and in the sea;
For in one Spirit were we all baptized into one body, whether Jews or Greeks, whether bond or free; and were all made to drink of one Spirit.
Else what shall they do that are baptized for the dead? If the dead are not raised at all, why then are they baptized for them?
For as many of you as were baptized into Christ did put on Christ.