Not what it sounds like.
These are not people who are preaching for "gayness" or anything like that, just a gay couple who have been chosen by a Finnish missionary organisation to be sent to Cambodia.
Naturally some christians do not agree that a gay person (or even worse two gay men living together!) could spread the word of Jesus.
When news about this broke the Vicar who was the head of the organisation made an official apology...
...To the couple, since this was not supposed to be made public untill the couple had given their permission for it but somehow the papers got word of it even before they have been blessed as missionaries. In fact the Vicar defended his choice by pointing out that even according to the laws of Finland the most competent person must be chosen to a job and that they cannot discriminate based on a persons sexual preference and that a persons family life is not something the employer needs to know. (Although they did obviously know about them being a samesex couple and simply did not think that this is a disqualifying factor.)
I can't seem to find an english version of the original story but here is one follow-up:
http://yle.fi/uutiset/hate_mail_sent_to_bishop_for_blessing_same-sex_missionary_couple/6673537(No actual death threats, but several claims of her having lost her seat in heaven etc.)
Not that suprising, really. Another missionary organisation has already condmened this decision and this will presumable cause yet another fight inside the Finnish Lutheran church.
In the end this is yet another sign that many Finnish people and even Finnish christians are not the least bothered by gay people. We have an extremely loud minority but even in the church they are being outnumbered. Soon they will have to branch off from the main Lutheran church (or join the Catholic or the Orthodox church like some have already done.) if they wish to find a place where the gay are unwelcome.