Command? or principle?

In Leviticus 19:19 the underlying principle being communicated involves the ancient Near Eastern idea that mixed things belong to the divine realm. Divine creatures are composites of various kinds of animals, and cloth woven from two kinds of thread is used in the tabernacle and the vestment of the priests. The underlying principle in this case is that divine things should not be put to ordinary, mundane use. Although the underlying principles vary by context, all of the instructions in Leviticus should be read in this way. They are hypothetical examples designed to communicate abstract principles, not commands to be obeyed.— The Lost World of the Israelite Conquest, 92–93

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They could be opening a real can of worms here...
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