I have been sort of collecting these passages this semester, and perhaps I will find some time to post some of the earlier ones I have discussed in class (Gen. 6:1-4; Exod. 4:24-26; most of 1 Kings 17-2 Kings 10, etc.). One such passage is for my class this friday. When reading Ezekiel's reasoning for the exile, which it is fruitful to compare to Isaiah's and Jeremiah's warnings, one finds that the problem is that the people have persistently and consistently not walked in God's ordinances and statutes (cf. Leviticus 18:1-5) and have not kept the sabbaths (the use is in the plural like in the Holiness writings). This problem was there since Egypt--that is, in Ezekiel 20, Ezekiel basically argues that there has not been a time when the Israelites actually did follow God's ordinances, statues, and properly revered God's sabbaths. This differs from the emphases in Jeremiah and Isaiah that the reason for (impending) destruction is lack of justice: not properly caring for the vulnerable in society, such as orphans, widows, and the oppressed. Although this surely can be included in Ezekiel's statutes and ordinances, the emphasis for Ezekiel tends to be more cultic: proper and improper worship. But in the process there is quite a difficult line:
and I defiled them through their very gifts in making them offer by fire all their first-born, that I might horrify them; I did it that they might know that I am the LORD. (Ezek. 20:26)
Ezekiel, as noted, is very close on most topics to the Holiness Code (Leviticus 17-26), but on this point, compare Lev. 18:21 (see also Deut. 18:10):
You shall not give any of your children to devote them by fire to Molech, and so profane the name of your God: I am the LORD.
It is unclear what offering one's child to Molech would be. Whether this is another deity or the LORD as king (Melech). In both passages, the practice offering one's child by fire (as a burnt offering) has a negative valuation. One might argue that "first-born" for Ezekiel is not one's own human children, but this would not explain why it is so horrifying. It takes the offering of the first-born sons (e.g., Exod. 22:29) very literally.
For Ezekiel, this burnt offering is a command from God; in Leviticus it is forbidden by God. While in Leviticus, this action would profane God's name, it is interesting to note that the reasoning behind God's actions in Ezekiel 20 throughout--the reason why God does not continually punish the Israelites--is for the sake of God's name. Thus while in Leviticus, offering one's children as a burnt offering profanes God, as a divine command in Ezekiel, it defiles the people.
So, let's run down the checklist for this one verse: God demands burnt offering of one's first-born child; God is trying to horrify; God is trying to defile through the very mechanisms of sacrifice. That is, sacrifice, which is supposed to remove one's ritual impurity and moral defilements is here the very means of that defilement (and again portrayed as a divine command).
These two too contrary passages end on the same Holiness note: "I am the LORD." It is a statement that punctuates the Holiness code; it is the exclamation point and the underlying powerful reason why one should obey. For the Ezekiel passage, this divinely inflicted horror is so that the people can actually KNOW that "I am the LORD." It is the ultimate expression of divine authority. God is demonstrating ultimacy by being beyond morality, ethics, and even purity and defilement. Horror demonstrates God's terrible power, instilling fear.