I do not believe that it is a requisite for Israeli citizenship for one to be Jewish.

Taken from the Israeli Immigrations website:

Acquisition of Nationality by Naturalization

Adults may acquire Israeli citizenship by naturalization at the discretion of the Minister of the Interior and subject to a number of requirements, such as:

> they must have resided in Israel for three years out of five years preceding the day of submission of the application;

> they are entitled to reside in Israel permanently and have settled or intended to settle in Israel;

> they have renounced their prior nationality, or have proved that they will cease to be foreign nationals upon becoming Israeli citizens.

The Minister of the Interior may exempt an applicant from some of these requirements.

However, as it states above, one cannot be posses Duel-Citizenship.