What is harder to understand is what reason other than homophobia could make elders view homosexuality as a far more grave sin than others "gross wrongdoing", including adultery. All you have to do is read Malachi chapter 3 to understand how God views adultery (not two people not married to each other who found themselves in the wrong place at the same time, but deliberate deceit and years of cheating their respective spouses). He detests it. There is nothing in the Scriptures that alludes to some special onus on homosexuality versus fornication.
Elders will apply the most severe punishment on someone who was involved with someone else homosexually but will let people totally skate on other forms of immorality - never mind the other kinds of "gross wrongdoing" that just get ignored. Where are the "judges for righteousness" that Jehovah has supposedly appointed here (Duet 1:16).
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