Members of Tamaki's Destiny Church have recently been charged for destroying rainbow crossings in Gisborne and Auckland, and were responsible for a series of drag events being cancelled around the country.
The image of the child and the head are part of promotion for an event last night in New Plymouth.
The next event is to be held in Whanganui on Tuesday evening.
Promotional material on social media for the events uses phrases like "Time to kill", "It's time to gather heads" and "I want a head (trophy) on my mantlepiece (sic)!"
But Tamaki said the imagery was used figuratively and the phrase "Time to kill" was from the Bible.
Whanganui Mayor Andrew Tripe said the council opposed any events which might seek to cause division within the community.
"The graphic imagery in their promotion suggests this is the case. However, we have no ability to stop this event because it is at a private venue."
In a video of the New Plymouth event Tamaki preaches against transgender and rainbow community rights; puberty blockers; Palestine; and the environmental movement.
It appears he is implying that these are the 'Goliath', and his own movement, Destiny Church, is the 'David'.
Tamaki said in a statement "The story and imagery of David and Goliath is used figuratively. I have stated many times that Destiny Church and I do not hate anybody in the rainbow community. We are always peaceful, never hateful.
"Any terminology I ever use in relation to warfare…is in relation to the spiritual battle we face every day as Christians. It is not directed at any individual. The term 'Time to Kill' also is a direct quote from the Bible found in Ecclesiastes 3:1-3. '…there is a time to kill, a time to heal…'."
The giant he referred to in New Zealand was a "a spirit that wants to sexualise our children and young people. To kill, means to bring to an end…followed by a time to heal".
'Dehumanising talk' - local fears for safety
A member of the local rainbow community, who did not want to be named but identified as non-binary, said the church's promotional material was extremely concerning.
"[This is] dehumanising talk, where we're the paedophiles, and we're the filth, and we're the degenerates. And there's a logical end point where we get attacked on the street."
They were planning on avoiding town for the next few days, and said they were especially worried for younger rainbow community members.
"I think Tamaki has gone far beyond expressing his free speech."