There is a Verse in Scripture, that is MORE misinterpreted than any other VERSE. So before you Take Up stones to cast at me, HEAR ME OUT.
Ephesians 4:4-6 (HCSB)
4 There is one body and one Spirit—just as you were called to one hope at your calling—
5 one Lord, one faith, one baptism,
6 one God and Father of all, who is above all and through all and in all.
That one baptism is not talking about Christian Water Baptism, it is Talking about when we were first SAVED, the Holy Spirit IMMERSED {Baptized} us into the Spiritual Body of Jesus Christ. I will prove it with the Scriptures. Yes, Christian Water Baptism, is important in that after we ARE SAVED, we are to Publically personally Identify that we HAVE RECEIVED CHRIST AS LORD OF OUR LIVES. But that is not the Baptism that SAVES, even though it should be one of the first steps of Walking In Christ. However, it is the IMMERSION INTO THE SPIRITUAL Body of Christ, of which HE is the Head, that did SAVE US.
1 Corinthians 12:12-14 (HCSB)
12 For as the body is one and has many parts, and all the parts of that body, though many, are one body—so also is Christ.
13 For we were all baptized by one Spirit into one body—whether Jews or Greeks, whether slaves or free—and we were all made to drink of one Spirit.
14 So the body is not one part but many.
EVEN THE THIEF ON THE CROSS WAS IMMERSED INTO THE SPIRITUAL BODY OF CHRIST WHILE HE WAS STILL ON THE CROSS.
So that is the one baptism that SAVES, and ALL of us who have received HIM as LORD, have received that Spiritual Baptism.
Therefore the ONE BAPTISM in Eph 4:5, has to be talking about that BAPTISM that was performed by the HOLY SPIRIT.
Ephesians 1:13-14 (NASB)
13 In Him, [.NOTICE: the H.S. Baptized you into Him.] you also, after listening to the message of truth, the gospel of your salvation—having also believed, you were sealed in Him with the Holy Spirit of promise,
14 who is given as a pledge of our inheritance, with a view to the redemption of God's own possession, to the praise of His glory.
When the GOSPEL of our Salvation, came into our Hearts with understanding, the Holy Spirit immediately immersed us into the Body of Christ; LONG BEFORE YOU EVER DECIDED TO CLIMB INTO A BAPTISTERY.