Deuteronomy 4:
23 Take heed unto yourselves, lest ye forget the covenant of the LORD your God, which he made with you, and make you a graven image, or the likeness of any thing, which the LORD thy God hath forbidden thee.
24 For the LORD thy God is a consuming fire, even a jealous God.
25 When thou shalt beget children, and children's children, and ye shall have remained long in the land, and shall corrupt yourselves, and make a graven image, or the likeness of any thing, and shall do evil in the sight of the LORD thy God, to provoke him to anger:
26 I call heaven and earth to witness against you this day, that ye shall soon utterly perish from off the land whereunto ye go over Jordan to possess it; ye shall not prolong your days upon it, but shall utterly be destroyed.
27 And the LORD shall scatter you among the nations, and ye shall be left few in number among the heathen, whither the LORD shall lead you.
28 And there ye shall serve gods, the work of men's hands, wood and stone, which neither see, nor hear, nor eat, nor smell.
In other words, "I am a jealous God. Worshiping other gods will provoke me into a jealous rage, and I will cause you to perish." It's perfectly true that the same words applied to a spouse would be considered horrific:
23 Take heed unto yourselves, lest ye forget the covenant [your husband], which he made with you, and [look at pictures of other men, which your husband has forbidden].
24 For [your husband] is a consuming fire, even a jealous [husband].
25 When thou shalt beget children, and children's children, and ye shall have remained long in [your husband's house], and shall corrupt yoursel[f], and [look at pictures of men], or the likeness of any [other men], and shall do evil in the sight of [your husband], to provoke him to anger:
26 I call heaven and earth to witness against you this day, that ye shall soon utterly perish from [your husband's house] whereunto ye go over [to live]; ye shall not prolong your days [in] it, but shall utterly be destroyed.
27 And [your husband] shall [send you out into the streets], and ye shall be... among the [homeless], whither [your husband] shall lead you.
28 And there ye shall [date other men]...
If my wife wants to see other men, it's a terrible thing, and I would indeed consider leaving her (or kicking her out) as described in (my paraphrased) verse 27. However, if I laid a finger on her, let alone caused her to "utterly perish," it would be considered a horrific crime in the eyes of men. The law of Moses ambiguously would give me the option of either having her stoned, or simply divorcing her, although Matthew does praise Joseph for choosing the latter instead of the former.
We could argue that the whole "utterly perish" thing is mitigated by the fact that the general thrust of the passage is about exile, rather than destruction. Alongside that, though, we would need to consider God's praise of Phinehas for killing the man of Israel and the Midianitish woman, "that I consumed not the children of Israel in my jealousy." We would also have to consider the provision of capital punishment for idolatry, which in effect says, "Worship only me, or these people of mine will stone you to death." Again, if I stoned my wife for adultery, it would be considered a horrible crime today--probably even by Christadelphians.
I don't have a perfect answer for this objection, although I have one that satisfies me (and not, I think, folks like Evangelion, who have heard it before). Namely, God is to humans as humans are to cattle. Just as we can slaughter cattle for no better reason than we're feeling peckish and want a hamburger, so God can slaughter human cattle for any reason that suits Him. There be those who object that slaughtering cattle to make snack foods is wrong; without any attempt at moral justification whatsoever, I reply that it is in fact oh, so right.
Viewed from my perspective, then, it IS a horrible crime for humans to kill each other over jealousy. It ISN'T a horrible crime for gods (of which there happens to be only one). Humans may object to this--sorry Ken!--but so what? If cattle could talk, they would no doubt object to cheeseburgers.