‘You (ye) shall not eat of anything that dies of itself: you (thou) may give it to the resident alien who is within your gates, that he may eat it; or you may sell it to a foreigner, for you (thou) are a holy people to Yahweh your God.'
They must thus not eat of what dies of itself. What has died is already committed to Yahweh in death, and is lifeless, and is not suitable for them as a holy people to Yahweh their God, for He is the Lord of life. They must only eat that which has life, and of which they have been able to commit the blood, and in cases of things that died of themselves the blood would not have been properly dealt with. However resident aliens and foreigners were not a holy people, therefore such food could be given to the one or sold to the other. Note the distinction. The resident alien must be cared for, the foreigner must pay for what he gets.
“For you (thou) are a holy people to Yahweh your God.” This is also cited in Deuteronomy 14:2. In view of its placing in the analysis this is remarkable confirmation of the chiastic framework (otherwise why just here?) and doubly emphasises the holiness of His people.
Here their being a holy people contrasts with resident aliens and foreigners (both of whom are not proselytes, otherwise they would be ‘holy people'). Here then the stress is very much on the fact that Yahweh's people keep to a pure environment and only eat what comes from it.
‘You (thou) shall not boil a kid in its mother's milk.'
See Exodus 23:9; Exodus 34:26. Its being placed here connects with the idea that Israel are His holy people (just as verse 1 connects with Deuteronomy 14:2 and with Yahweh's fatherhood of His people. Here though the son is of a clean beast. It is thus not to be put into an unsuitable environment. But the comparison with verse 1 would suggest that it has religious connections.
Whether this does refer to a pagan mystical practise, or is just seen as unseemly in view of the relationship between mother and kid is debated. For a kid to be boiled in the very milk which was supposed to feed it and be its source of life meant that it was not in its ‘proper sphere'. It would be an ‘unclean' practise, and unwholesome. A person would have to be totally insensitive to do such a thing. So in view of the emphasis on outward appearance in this chapter the latter could well be the case. The example sometimes cited from Ugarit is of doubtful translation and relevance. But the way in which it is connected with the Passover in Exodus 23:19 with 15 may indicate a mystical and unacceptable practise (see commentary on that passage).
So the emphasis all through this passage has been on doing what is seemly, and avoiding all appearance of lowering themselves to the level of the world of predatorial beasts and birds, and creeping things, and death. Especially of avoiding all things that were seen as consigned to the dust to which the serpent had originally been consigned, and the avoidance of contact with the sphere of ‘the dust of death'. In Leviticus the connection with Genesis 1-3 is more apparent. They were to look Godward and not earthward. This would then protect them from disease and from idolatry, but equally importantly, from being unwholesome. The aim of such teaching was not only to prevent their eating what might physically harm them, but to give them an attitude to life that was pure.
The lesson for us is that our lives too should have the appearance of the heavenly. We too should abstain from all appearance of evil. We now have a different conception of creation so that the specific restrictions no longer apply, nor would they teach the same lessons to us as to those who lived so close to nature. What we are called on to avoid is rather the lowering of ourselves in the moral sphere. We too are thus to be ‘clean'.
Jesus, in another context, makes this clear. He stressed that it is what comes from men's hearts that defiles (Mark 7:14-23), and must therefore be avoided. Acts 10:14-15 also demonstrates that nothing in creation is ‘unclean' of itself. It becomes unclean by what it does. There is, of course, still the need to discriminate, but on a different basis depending on health risk.