A couple months ago, something I was reading referred in a footnote to an extended note by Joyce Baldwin in her Zechariah commentary on jealousy. Baldwin's discussion was excellent, as her work usually is, but one thing stood out. I'll quote the two relevant paragraphs and then comment further. Some of the formatting on her Hebrew transliterations isn't exact, but I've tried to do the best I could with the tools at my disposal.
The Hebrew word qin'a is translated in RSV by 'jealousy', 'zeal', and 'fury'. Its root is probably connected with an Arabic word meaning to become intensely red (or black) with dye, and so by derivation it draws attention to the colour produced in the face by deep emotion. The Greek zeloo, 'to be jealous', derived from zeo, 'to boil', also expresses deep feeling. From it the English words 'zeal' and 'jealousy' are both derived, so indicating that the emotion can be directed to good or bad ends. When it is self-regarding it results in intense hatred, but when it is concerned for others it becomes a power capable of accomplishing the most noble deeds.
It is significant that God is first spoken of as 'jealous' at the giving of the covenant code (Ex. 20:5; 34:14; Dt 5:9), when the special relationship was established between the Lord and His people, Israel. Because they are His, they can belong to no-one else, hence the prohibition of idolatry and the sanctions against it in the third commandment; but these are followed by assurances of 'steadfast love to thousands of those who love me and keep my commandments' (Ex 20:6). God's jealousy is a measure of the intensity of His love towards those with whom He has entered in covenant. So great is His love that He cannot be indifferent if they spurn Him by disobedience or sheet carelessness. [Joyce Baldwin, Haggai, Zechariah, Malachi, pp.101-102]
This distinction between other-motivated jealousy and self-motivated jealousy strikes me as an interesting contrast with John Piper's views on God's motivations. He reduces God's motivations to one: God's passion for his glory. I think Piper would say that God does things for the sake of others, but ultimately he insists that such motivations are really only surface-level. The deeper motivation for doing things for the sake of others is that doing things for the sake of others increases God's glory. So the other-motivated concerns are still there, but there's nothing deep about them. They exist only because they further God's glory, and thus all of God's motivations are at the deepest level self-motivated.
I don't think Piper would deny Baldwin's contention that God's jealousy reflects his love, but I think he would say that God's love is in turn motivated purely by his concern for his glory. I think that flies in the face of how the scriptures present God's love, and I think Baldwin is trying to push in the other direction. God's jealousy, as far as she is concerned, is not in any way motivated by his glory. That would be directed to a bad end and would produce intense hatred, according to her account.
I think she's right that the biblical statements on this reveal an other-centeredness in God's jealousy, and that does contrast with Piper's reduction of God's motivations to concern for his glory. Piper does emphasize God's concern for his glory to the point of ignoring and denying any deep other-centeredness in God's motivations. I wonder, however, if Baldwin errs on the opposite side. If I had to err on either side, I think I'd choose hers. I'm more sure that there's a deep other-centeredness in God's motivations than I am that God has any purely self-centered motivations. After all, even God's eternal intra-Trinitarian relations apart from creation are other-centered in the sense of each person of the Trinity relating to other persons of the Trinity. But might there be some ways that God is moved to jealousy independently of his concern for the people he's jealous of? Might it not be that the motivation Piper says God has is among God's motivations? Baldwin seems to me to be ruling that out entirely, and acknowledging that God's love is part of his jealousy may not require saying that the only motivation for his jealousy is love.