A friend told me of his church doing just that. He listened as a Jewish man lectured on the secret meaning of the Bible until my friend could take no more. There was a time (Luther's day) when the whole incident would never have happened.
The Bible is very clear that during the church age the people of Israel have been blinded to the truth about their Messiah. Some day they will look upon Him whom they have rejected and killed, and they will mourn. But since they are blinded to the truth at present, why seek them out to lecture us on the Bible?
Sounds like a rhetorical question, but in this case I believe I know exactly why. In Malachi Martin's novel Windswept House, he has a great tell-all scene of a Grand Lodge in the Holy Land, where representatives of Islam, Judaism, and nominal Christians, meet for "services". The unity of religions and of the eccumene--the entire inhabited earth--is Antichrist's great goal.
After God's people are in heaven or in the camp of the saints on earth, this goal will be achieved, briefly. Like setting out a piece of jellied bread to attract the flies so you can swat them all at one time, God will allow the evil ones to unite for one brief moment. Like in the wheat and tares parable, first the harvest, then the tares will be burned.
So how does this apply to my friend's church? Though nominally Presbyterian, it was founded by Masons. In its entryway there was a sturdy cage containing the Masonic paraphernalia of its founders, their aprons and trowels. It had been established by Masons and their Godless agendas were still ongoing--unity above all.
When my friend and his wife announced that they were leaving because of such rampant paganism, they were asked, "So what's the big deal? So what?" They finally learned why we cannot worship together.