In response to WKK..
Please keep in mind that anger does not equal hate. One can, (especially God) be angry and still love the person you are angry with.
As far as God being angry and vengeful, I believe that the word vengeful, in its proper context here, is not meant as a negative ( ie REvenge) but as a term of discipline, or even as a term of justice (as in God will punish sin)
"You shall not bow down to them or worship them, for I, the Lord your God, am a jealous God, punishing the children for the sin of the fathers to the third and fourth generation of those who hate me..." Deut 5:9
And yes, our God is a jealous God. He will not accept sharing praise with another god.
"Do not worship any other god, for the Lord, whose name is Jealous, is a jealous God." Ex 34; 14
Having jealousy as an emotion may not be a bad thing. We think of jealousy as a negative emotion, reserved for those poeple that struggle with insecurity issues. Jealousy has its place as a valid emotion, but we as human beings have distorted jealousy from its proper use into a tool of manipulation borne from insecurity. Here is a healthy example of jealousy-
A wife has a lunch date with an old friend (male) alone. Husband expresses his concerns about her going for lunch with a male friend. He has a valid concern, and has expressed his jealousy in a healthy way. If wife decides to continue on with the lunch date, then there will be damage to the relationship.
Our God is a jealous God and he will punish sin. For example, if we decide to damage our relationship with him by worshipping false gods then we have brought upon ourselves his vengence (or retribution, or judgement or how ever you want to translate it).
Hope this helps.