Hours after the attack, 100 or so Roman Catholics gathered to pray in the rain in front of the ruined billboard, which had shown Mary gasping in shock as she examined a pregnancy testing kit.
The billboard outside the Anglican church of St Matthew's in the City, in central Auckland, New Zealand, had drawn thousands of angry comments as well as messages of support from around the world.
Arthur Skinner, a member of an organisation calling itself the Catholic Action Group, who described the Renaissance-style picture as "satanic", was photographed attacking it.
"Yes, it is vandalism," Mr Skinner proclaimed proudly outside the church.
"I'm guilty. If they want to arrest me, be my guest.
"If it comes to that, I believe in being persecuted for my faith."
He told the crowd of worshippers: "We are traditional Catholics.
"We don't look for trouble, but watch out if you start this sort of thing."
Mr Skinner said those responsible for the poster, which was created by an advertising agency, would "certainly burn in hell" if they did not repent.
Many of the people who knelt on a wet pavement under umbrellas to pray and say the "Hail Mary" rosary condemned the poster as blasphemous.
The Rev Glynn Cardy, vicar of St Matthew's, who had earlier described the poster as "thought provoking", told reporters: "I'm disappointed that there is not more tolerance of different views.
"They obviously feel strongly about it.
"I'm just disappointed that strength of feeling has led to vandalism."
He said St Matthew's would "need to think about" whether to replace the poster.
Two years ago a billboard outside the same church depicting Joseph and Mary in bed after sex had to be taken down after it was attacked several times by outraged Christians.
