Question:I was questioned about baptizing in a pool as opposed to baptizing in streams or other water sources. I did not know what Scripture to use to affirm pool baptism. Can you help?
The word "baptize" means to immerse. The medium into which believes are baptized is water. "Can anyone forbid water, that these should not be baptized who have received the Holy Spirit just as we have?" (Acts 10:47). A specific type of water is not commanded, so to add such a requirement is to add restrictions where God has not. The argument would be equivalent to taking the command to sing and saying we can only sing songs which come from the book of Psalms. What is important is that there is sufficient water to immerse the person. "Now John also was baptizing in Aenon near Salim, because there was much water there. And they came and were baptized" (John 3:23).
If the source of water was important, then it would be required to show either a command where the source was restricted or examples where the source was important to the event.
In Acts 2, three thousand were baptized in Jerusalem. This city does not have streams or rivers flowing through it, but there were a number of pools and these were what was likely used.