The scriptures he is posting seem to me to be directed at people who suspect him. HE is going through trying times, needs strength to endure what HE is going through, needs to be reminded that HIS difficult times will end. He's telling other people not to give into temptations of mob-mentality to falsely accuse him, and instead to insist on the truth.
I don't think the scripture are aimed at the killer or his wife, but at the public to leave him alone and at himself to give him strength to endure the public scrutiny.
I go either way with my reactions - it could be a man in pure pain at the sudden loss of his wife/mother of his children to a violent death. People grieve differently, and finding comfort and strength in scripture is not uncommon. Or, the FB postings could be a show.
As with almost everything on this case, I'm on the fence. I'm getting slinters in tender places from sliding from one side of the fence to the other.
Hoping for a break in the case soon.