Are they Catholic? Dunk them well and pray that it will serve to cleanse them of their popish ways.
Are they Anglican? Send them under the water and command them to drink no more.
Are they Presbyterian? Bury them in the baptismal pool and tell them that it’s a good thing they didn’t show up to heaven merely sprinkled.
Are they Methodist? Tell them grab their noses and prepare for immersion for their baby baptism just doesn’t cut it.
Are they Southern Baptist? Wash them again and pray that the stench of their old NIV will not linger upon them.
Are they Independent Fundamental Pre-Trip King-James-Only Soulwinning Baptists? If they have walked the aisle again and prayed The Prayer again then baptise them again just in case.
For the baptism of water may only be a symbol to us but it’s useful for separating the congregation of the blessed from those who will likely be left standing outside the gate. It’s not so much what you’re being baptized into, after all. It’s what you’re being baptized against.