What does it mean?
1) I’ve been initiated
Baptism is a ceremony of initiation, demonstrating our entrance into the Body of Christ where Jesus is Lord. We are not baptised ‘into a denomination’, but ‘into Christ’ (Romans 6:3), and thus into His body, the church.
2) I’ve been sealed
Baptism should confirm and strengthen your faith. Let’s say, here’s a letter representing you, and an envelope representing Christ. The letter is placed in the envelope, just as in conversion you are placed in Christ. Then the envelope is sealed. That’s like water baptism. It makes you feel secure.
3) I’ve been cleansed
Bathing the body is an essential part of hygiene. Conversion, ‘the washing of rebirth’ (Titus 3:5), deals with the grime of sin, and baptism reminds you that you are now to live as a cleansed person.
Read Ananias’s words to Paul at his baptism (Acts 22:16). They show how new birth and baptism belong together. We must not separate them. Once you’re born again you qualify for it.
4) I confess Christ
New birth may be in the seclusion of your own room, but you can’t have a ‘private baptism’. In the New Testament it was in rivers and city pools. It’s no ‘hush-hush’ affair. It’s like an enlisted soldier putting on the uniform (Galatians 3:27). You can’t wear the uniform and be a secret soldier.
5) I am united with Christ
I am united with Christ in his death and resurrection, as in our reading (Romans 6:1-22). Think of the pool as the grave and your body as the corpse. What do you do with the corpse? Bury it. What do you do with your old life, with its sinful ways, now that you are a Christian? Bury it in the act of baptism.
Christ rose again. Going under is followed by coming up. That’s reassuring! United with Christ you rise to ‘live a new life’ (Romans 6:4). Believe for the symbolic act to be a reality in your life.