... Christians tend to
translate the term as "zealous" in Exod. 20:5 ...
Liz, in view of what David and Harold have written, can you substantiate
this from a number of English Bible translations? Of the 18 English
versions at Bible Gateway, all generally Protestant Christian,
http://www.biblegateway.com/passage/?search=exodus%2020:5;&version=72;
nearly all translate "jealous". Only Young's Literal has "zealous", and
CEV has a periphrastic rendering, as does TEV (not at that site).