Jesus drove out some demons into a herd of swine, which ran down the bluff, into the water and drowned. Could not such an action be construed as cruelty to animals?
Well, the pigs are not really the point of the story, and we ought not to get too focused on them. More to the point of the story is the authority of Jesus Christ to cast out demons.
Thus, one might respond to the cruelty charge, that the Lord God has the capacity and authority to do this to the pigs, just as you and I might go to our garden, uproot withered tomatoes and replace them with corn. Further, having authority over animals, we also lead pigs to slaughterhouses.
One might still argue that driving the demons into the pigs was an arbitrary and unnecessary act by Jesus. But perhaps the Lord has reasons. For example, he may have wished to inspire a holy fear in those who saw the action. It was surely a memorable action, and while the townsfolk initially reacted with fear, it would seem they later welcome Jesus back with faith (Mk 5:17‐20; 7:31). Hence, Jesus makes use of the animals to bring blessings to human beings, which is fitting.
Culturally, pigs were considered by the Jewish people to be unclean animals. Thus, the pigs also help to fittingly illustrate the uncleanness of demons, and the fate of those persisting in uncleanness.
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