Israel does not have an official religion. 1992 legislation defined the country as Jewish & democratic - but is this instance of Jewish being used as a religious, a racial, or ethnic/cultural term.
The majority of the citizens call themselves Jewish - but as far as their religious practices are concerned they range from secular (nonobservant) to the ultra-Orthodox.
The court system includes religious courts: "Jurisdiction in matters of personal status (marriage, divorce, maintenance, guardianship, adoption) vested in judicial institutions of the respective religious communities: Jewish rabbinical courts, Muslim sharia courts, Druze religious courts, ecclesiastical courts of the ten recognized Christian communities in Israel." http://www.mfa.gov.il/mfa/aboutisrael/state/pages/the%20state-%20judiciary-%20the%20court%20system.aspx
Accessed 10 May 2017.
Dayanim [Rabbinical Courts Judges] Act 1955 s10 "I hereby undertake to be loyal to the State of Israel, to justly adjudicate among the people, to remain impartial, and not to unjustly prefer one side over the other."
"The Israeli legal system is unique among modern legal systems in the utilization of various personal status laws in the area of family law, applied by religious courts. This phenomenon has historical and political roots: it existed under Ottoman rule and was retained by the British after they conquered the country.
The basic source for the application of the personal status law and the jurisdiction of the various religious courts is found in the Palestine Order in Council (1922). This order provides that "jurisdiction in matters of personal status shall be exercised... by the courts of the religious communities".
The order also grants jurisdiction to the District Courts in matters of personal status for foreigners who are non-Muslims, stating that they "shall apply the personal law of the parties concerned". Regarding foreigners, this was defined as "the law of his nationality". Case law determined that regarding non-foreigners, "the court ... have... to apply the religious or communal law of the parties".
The Palestine Order in Council recognized eleven religious communities: Jewish, Muslim, and nine Christian denominations. The Israeli government added the Presbyterian Evangelical Church and the Ba'hai to this list. The Knesset also enacted a law vesting jurisdiction in the Druze religious courts."
Section on "Religious Courts" on The Judiciary: The Court System on Israeli Ministry of Foreign Affairs website.
<http://www.mfa.gov.il/mfa/aboutisrael/state/democracy/pages/the%20judiciary-%20the%20court%20system.aspx> Accessed 10 May 2017
Izhak Englard Law and Religion in Israel (1987) 35 The American Journal of Comparative Law 185-208
Amnon Rubinstein Law and Religion in Israel (1967) 2 Israel law review 380-414