Take Heart!
From Christian Vegetarian Association (CVA)

Killing the fatted calf in celebration of the Prodigal Son’s return: Luke 15:23

(Excerpt of CVA’s responses to some frequent biblically based objections to our position.)

Eating the “fatted calf” was a sign of joy and celebration that, presumably, Jesus’ audience understood. This was a parable, and no calf was actually killed. When people today use language and metaphors such as “to kill two birds with one stone,” that doesn’t mean that we actually approve of such behavior. Furthermore, if Jesus had approved of animal agriculture in his day, it would not follow that he would endorse modern factory farming.

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