Must I be water baptized to be saved?

Paul taught of only ONE baptism. What baptism is that? A waterless baptism of the Holy Spirit that places you into the Body of Christ at the moment you are saved. This is unique to the Body of Christ who receive salvation through the grace gospel. For the 12-apostles in the book of Acts, it was always TWO baptisms. The 12-apostles could never separate baptism (water and Spirit) from their gospel. Consider the instructions and order of the Kingdom gospel, 

Acts 2:38 Then Peter said unto them, Repent, and be baptized every one of you in the name of Jesus Christ for the remission of sins, and ye shall receive the gift of the Holy Ghost.

Notice that after a Jew repented, they had to be baptized in water. Water baptism was a requirement in the Kingdom gospel as it was for the cleansing for priesthood (Exo.19:6), something that ALL Jews had to do, 

Acts 8:14 Now when the apostles which were at Jerusalem heard that Samaria had received the word of God, they sent unto them Peter and John: 15 Who, when they were come down, prayed for them, that they might receive the Holy Ghost: 16 (For as yet he was fallen upon none of them: only they were [water] baptized in the name of the Lord Jesus.) 17 Then laid they their hands on them, and they received the Holy Ghost.    

After water baptism, they could receive the baptism of the Holy Spirit to begin the fulfilment of the new covenant according to Jer.31:31-34 and Ezek.36:24-27. This was ingrafted into the gospel, into the minds, and into the teachings of the 12-apostles.

Now Paul comes along and says that in his gospel and doctrine, water baptism is no longer required and that there is only ONE baptism,

1 Cor.1:17 For Christ sent me not to baptize, but to preach the gospel: not with wisdom of words, lest the cross of Christ should be made of none effect.

Eph.4:4-5 There is one body, and one Spirit, even as ye are called in one hope of your calling; 5 One Lord, one faith, one baptism, ...

Paul teaches that this one baptism is the baptism performed BY the Holy Spirit (1 Cor.12:13) in order to immerse the believer into the Body of Christ. There is no water involved, there is no priest or pastor or elder involved. It is a supernatural event that happens at the moment of salvation. 

Paul says that this is the only baptism necessary for the member of the Body of Christ. Water baptism has no real part in this dispensation because we are not called to be priests and do not need this ordinance to be cleansed for priesthood. Can you see the enormous difference again between the Kingdom program and the Grace program? If you do not recognize these dispensational changes and you try to mix up scripture and practices you end up with a huge mess! No wonder we have such arguments and controversy in the denominations today. Let me again remind you what Paul says about his unique apostleship and authority,

Rom 11:13 For I speak to you Gentiles, inasmuch as I am the apostle of the Gentiles, I magnify mine office: 

1 Cor.14:37 If any man think himself to be a prophet, or spiritual, let him acknowledge that the things that I write unto you are the commandments of the Lord. 38 But if any man be ignorant, let him be ignorant.