Shawn Ketcheson, the senior pastor at Trinity Bible Church of Ottawa, is one of the religious leaders accompanying Harper.
The smaller "official delegation," for whom airfare and accommodation costs are covered, includes 29 MPs, senators and staff, as well as Canadian Ambassador to Israel Vivian Bercovici and three policy advisers.
Ketcheson says on the church's website that he "will not water down the truth about Jesus and the life He brings." In past sermons, he's preached that homosexuality is a sexual perversion, quoting Bible verses.
Ketcheson argues the world is full of sexual perversion ranging from masturbation to sex outside of marriage to gay sex.
"God says one partner, one sex partner for life. That's basically what the word of God says. Basically that's what it says. That's what I get out of it," he said in an Oct. 30, 2011, sermon.
"Lesbianism. Women lying with other women. Scripture says it's wrong ... by the way, if you talk about the word of God as being right and you condemn this, then you're a hate-monger and you should be punished. That's how far we've gone to twisting the word of God," he said.
"The first way the wrath of God is revealed to humanity is as a consequence of sexual impurity, sexual perversion."
Delegates 'do not speak' for government
Harper's spokesman said some of the organizations and community leaders who are on the trip helped choose other delegates.
"In a delegation of this size you will always find different views, including views you do not agree with. Members of the delegation do not speak for the Government of Canada," Jason MacDonald said in an email to CBC News.
All 208 delegation members, plus the official delegation, have their accommodation paid for by the government.
Thirty members of the accompanying delegation have their travel paid for as well as their accommodation. The 31-person official delegation — including Harper and his wife Laureen — travel on the prime minister's plane.
About 30 members of the delegation are religious leaders, while around 50 appear to represent Jewish or other religious organizations in Canada. Many work with religious organizations as well as represent Canadian law firms or businesses.
Ketcheson isn't the only controversial member of the delegation.
It also includes Don Simmonds, chairman of Crossroads Christian Communications. His organization came under fire a year ago over a page on its website calling homosexuality a perversion. The group was getting government funding for work in Uganda, where gays and lesbians are under threat. Ugandan President Yoweri Museveni recently blocked a bill passed by parliament that would have jailed gays and lesbians for life.