This is pretty cultural and contextual -- in many social groups, at least on the west coast, holding hands and cuddling between friends is common. In some Asian countries you often see two boys walking down the street holding hands. I don't really agree that there's wisdom in teaching people jealousy over perfectly innocent behavior.

I said there's wisdom in ancient religions that have observed something about human nature that is otherwise hard to observe from a single individual's vantage point (not to mention trying to explain it in a concise/precise way). Saying it's equivalent to "teaching people jealousy" is illustrating my point, that teachings are often reduced and bastardized and then taught to children. Regardless, point taken and I agree there is cultural context, but even in hand-holding cultures, there will be an equivalent of an exterior but subtle show of attraction and the point Christians make (IMHO) is that you can be dishonest with yourself and then fall into the "trap", so it's almost a reductionist approach to morality, since if you intend never to "cheat" then why would you even be interested in the "first step", whatever that is for the culture.

As a Pākehā boy in Aotearoa in the 1960s I used to hold hands with my friends quite often. Especially if we were in conversation. Never even though twice about it. Eight years old

I challenge that notion as toxic. Holding hands, hugging or otherwise expressing physical closeness with "someone else" is considered normal, healthy and valuable in various cultures, including mine.

I don't understand this idea that a partner holding hands with a non-partner is inherently threatening or uncomfortable. On the contrary, seeing my partner being comfortable and able to express intimacy is a strong positive signal of their ability to form a secure attachment with me and other people dear to me.