William White said:
it really depends upon the nation.
If, in the UK or Scandinavia, you took a church to court for - example - inhibiting your human rights; then you would have a good chance of winning. The history of laws in such country has been a continual retreat of religion and continual increase of secular ideas. Try in a country where the courts are religious, you are on a hiding to nothing.
In the UK, the Church of England
is the State, and the Monarch is its temporal head, or Supreme Governor. That's the definition of an
establishment of religion. The spiritual head of the church remains the Archbishop of Canterbury, but the Monarch appoints the Archbishop on advice from the Prime Minister. Of course, the Monarch must be a member of the Church.
Norway and Sweden both had national establishments of religion, but these churches have only recently been granted greater autonomy and less entanglement in the affairs of state. Denmark still retains its officially established church, but other religions are free to practice.
Taking disputes arising from disagreements with canon law into a court of civil law usually gets short shrift from the latter. Courts are generally quite jealous of their respective jurisdictions and generally see no advantage in meddling outside their own realms.
In the US, the courts have generally let churches resolve their own internal disputes about religious doctrine according to their respective canons and codes. Where religious practice might conflict with criminal statutes, the record is a little less clear cut, but the courts still tend to err on the side of allowing freedom to practice religion, as in the cases where certain Indian tribes wished to continue using hallucinogens without running afoul of laws concerning possession or use of illegal drugs.
As one justice said about the US Supreme Court, "We are not final because we are infallible, but we are infallible only because we are final."
William White said:
Catholic priests are not allowed to marry, but married men are allowed to become catholic priests!
IIRC, only certain married men are allowed to become RC priests, generally those who were ordained in another church where clergy are permitted to marry, but then who decided to convert to Catholicism after marriage. The Church reportedly allowed this due to a dearth of priests coming from its own seminaries.
It would be interesting if religious "rules" were vigorously challenged in court.
You can challenge all you want, but the courts themselves are the final arbiters of which cases they decide to hear and which they decide to dismiss. If the courts decide a plaintiff is filing numerous frivolous nuisance suits, they will put such a party in jail, or fine them, or both.