The Children of God was a cult--uh, religious group--that in some regards was very similar to fundamentalist Christians. In many other regards, however, they were very similar to total lunatics.
The Children of God believed that whenever they were having sex, they were having it with Jesus. For some reason, rather than making them never want to have sex ever again, this made them do it often and indiscriminately. They must have been picturing young dashing Jesus, and not, blood covered vengeance seeking Jesus. In addition to Jesus-sex, there were allegations that members of the group doubled as prostitutes to raise money. Oh, and The Children of God were suspected of kidnapping children and shipping them off to other countries.
Late actor River Phoenix was raised in a Children of God compound, where he says he lost his virginity at age 4.
What were they thinking?
The thinking was probably that if all the Children of God did was have Jesus-themed sex, that'd eventually lead to more children. Since, according to River Pheonix, these kids start nailing as early as 4, the population would increase pretty quickly, and all of these new people would be raised on a diet of constant fucking too. Soon enough, the entire world would be run by a Children of God Sexocracy. The only possible drawback we can see is that the kids might turn out to be a little fucked up, like, oh we don't know, River and Joaquin Phoenix.
But other than that we don't see how that plan can fail. Just a matter of time until someone else picks up on the idea.