The bit about the Holy Spirit is not a reference to anything in Hebrew tradition. This is a reference to the Holy Spirit of Rome, which would have been in this specific case, carried by the legions. When Roman legions march in and push the Temple into the valley below, they will baptize the people, in the sense of overwhelming them, and they will baptize the people in the sense of causing them to perish, and they will do so in the name of the Holy Spirit of Rome.

This makes the name of the great man predicted by John clear: the name was Caesar. 

Before we step away from John, it’s important to note that baptism begins with and is characteristic of Christianity. This rite is mentioned here, and in a few other places, but there is no description of the rite beyond whatever we can imply with the word ‘baptism’. There are many elements of Christianity that derive from other cults and different traditions: baptism has no other origin. It started here, in the Book of Mark.  Pretty much everything else we associate with Christianity – the Bible, the cross, the passion, Mary worship, weddings, funerals – were all products of later ages. When it began, baptism may have been the only thing that distinguished Christianity from any other late 1st century Imperial cult.