Whoa, that's scary!
Frank Turek gave a passable response to the 'jealous' attribute.
But even this saw jealous in human terms: we see it, being selfish and self-obsessed, in a negative, and step past the minor meanings captured in the Shorter Oxford: "devoted, zealous...amorous, fond...protective of, careful in guarding, watchful over,...vigilant, watchful, careful" with a wonderful quote in the latter use from Helen Keller: "I guarded both doll and cradle with the most jealous care."
One is jealous of something important to oneself.
Contrast this in a marriage where the husband couldn't care less it he wife had relations with another man. He clearly wouldn't care much either for his wife or his marriage.
But there's a deeper context to this.
We are made for communion with God. This is our best life.
If we do not put God first in our lives, then we put ourselves...even if we say we put others, or things (our car, the earth...Pluto) first, we are putting the creature ahead of the creator, and the creature has nothing in it other than that which is from the Creator. It is therefore not worthy of our 'worship'. The great deceit of monism is that it merges all into matter and the self as a real person disappears, abusing God's creation and himself.
God's jealousy underlines our best; our worship is us living out our best, and praise flows from that as the excitement of being in the family of the creator and being in real relationship with him, knowing what is truly true.