If you're asking if it invites jewish energy even though it's christian, in all honesty I can't say for sure, even though I understand the connection. Crosses do not affect me in any way as they have no power behind them, it is only the pathetic people that usually wear them that irritate me (the whole, oh great, another one energy I'm sure you know so well). The only time I've ever been severely annoyed is the 6 pointed star necklaces, and even then my evil eye is enough to have them shrink under my gaze and stave them off.
Personally, I don't like to have the fucking things near me because they usually have the energy of desperate, low intelligence, ignorant and submissive people.