Isn’t it the case, though, that motions to confirm arbitration awards are generally decided according to the Federal Arbitration Act, or according to the state law of the forum? Why would it be appropriate for the court to eschew those laws and decide the motion to confirm according to Islamic law instead? Even if the contract said that the confirmation of any resulting award was to be determined according to Islamic law, how does the court have jurisdiction to review, interpret and apply religious doctrine? Supreme Court precedent says courts have no jurisdiction to resolve issues of religious doctrine. And, parties cannot, by contract or otherwise, confer subject matter jurisdiction on the court.
And, that's exactly what happened here. The judge confirmed the order of the arbiter (the rules that the arbiter may use may differ from state standard because of the application of the choice of law doctrine).
"Why would it be appropriate for the court to eschew those laws and decide the motion to confirm according to Islamic law instead?"
This starts to get into some pretty esoteric legal theory (and some of the theory is still very unsettled or evolving law, so I'll try to answer generally because it's not my area of practice...)
The court didn't eschew those laws, it affirmed them. Those laws allow for contractees to include a choice of law provision in their contract. They did, willingly. It went to arbitration, per the terms of the contract, and the court enforced the decision of the arbitration. This is exactly what the court should have done provided that the designated arbiter followed his/their arbitration procedures, and the contract wasn't entered under duress or coercion. These are the matters of fact, and principles of law that would have been reviewable by the court under the Federal Arbitration Act.
"Supreme Court precedent says courts have no jurisdiction to resolve issues of religious doctrine. And, parties cannot, by contract or otherwise, confer subject matter jurisdiction on the court."
Right, in Presbyterian Church in the United States v. Mary Elizabeth Blue Hull Memorial Presbyterian Church (1969), the central legal holding was that the 1A "bars the state from passing judgment in theological matters when judging property disputes involving religious organizations."
This is the primary reason that contractees then choose to select an arbitration forum to resolve these theological based disputes. The arbiter isn't similarly constrained by Presbyterian Church in the United States v. Mary Elizabeth Blue Hull Memorial Presbyterian Church (1969), But even with the afformention Court case, lower courts have carved out some limited exceptions, that have so far not been reversed on appeal. One lower courts has held...
[A] court can invoke a secular interpretation of church deeds, by-laws and canons, thereby avoiding judicial entanglement in issues of religious doctrine, polity and practice. When the application of this standard requires judicial involvement in a [religious] doctrinal question, however, it may not be relied upon. [P]rovisions in deeds or in denominations constitution for the reversion of local church property to the general church, if conditioned upon a finding of departure from doctrine, could not be civilly enforced [quoting and endorsing a concurring opinion in a different Supreme Court case].
This will probably all be resolved sometime in the future when the Court hears some of these cases stemming from the Anglican and Episcopal churches that are being brought by members who wish to take their local parish, and withdraw from the larger church because the larger church is ordaining homosexual priests and whatnot.
Will the Court allow these local parishes to violate their contracts on somekind of theological basis? I don't know. It should be interesting to watch it play out.