I dunno, it seems pretty clear cut to me.
We don't want a juror influenced by coercion of any kind, so they cannot consult politicians, clergy, or even their spouses when making their deciision. They don't get to see the newspapers or hear public opinion.
On the other hand they are told by law to use some sort of moral compass.
So can they think about the bible? Yeh. Can they tell the others about it? Probably. When I was on a jury we were allowed to debate or not as much as we wanted.
So the legal question was whether reading the bible amounted to coercion or undue influence.
I can't say I agree with the decision, but I guess I can see the issue.
It's so sad that American law is still based on mediaeval and pre-enlightenment English - and, to a lesser extent, French - law when both of those countries have long ago moved on from such primitive ways.
The reason why jury nullification has been so reviled by legal scholars for literally decades is because of how it has worked in the past. In Hitler's Germany, jury nullification was used in cases where Jews were harmed by "Aryans", no jury in Germany would find an "Aryan" guilty of harming a Jew. In the modern United States, jury nullification was used in cases where Southern blacks were harmed by white KKK members. No jury in the South would find for a black man who had been harmed by a white KKK member.
If we are to have rule of law, it must be rule of LAW, not rule of "keeping the nigras in their place" or whatever non-law criteria may be interjected via "jury nullification". And if the law is an ass, the correct answer is to change the law, not to ignore it.
-Badtux the Law Penguin