Went back and read the transcript, and I read a lot less into it than others than have suggested it means LE knows who the killer is, or that LE believes the killer is a clergyman or a father with girls. To me, most of what they said indicates that they they're back a few spots along the board and need help moving forward, and trying to use the odds in their favor. I hope I'm wrong and they're close to getting the killer, or that even if I'm not wrong, that the PC works magic and it prompts someone to provide information that leads to the killer.
....
Edited for brevity by myself.
....
If they're from the local area, odds are they have a Christian background and upbringing, and IMO, this part is trying to have it both ways - appealing to someone who may have some guilt or conscience to do the right thing or to hit at someone who has pride in feeling he exercised some sort of power over the girls or the girls' family by pointing out that he failed, as he didn't end their lives because they live on in Heaven.