Mark 1:8 is surely an interpolation
Posted: Sat Sep 02, 2017 10:31 am
(Mak 1:8)I baptize you with water, but he will baptize you with the Holy Spirit.”
Given:
1) the presence of the fire/holy spirit in Acts 2 during the Pentecost
1) the absence of any reference to a fire by Jesus in Mark (also only to remember that he is the guy predicted by John)
my conclusion is that Mark 1:8 is interpolation based on Acts.