The reverberation of the food court area made for a breath taking presentation.
Although confident that the singers were singing along with a recording of their own voices it was a great offering.
The libretto is quite literally from the Bible but the music began with Handel's spiritual inspiration, and (according to wiki) "fattened" by Mozart as late as 1759.
If you compare it to Andre Rieu's "Live From Radio City Music Hall" version you can see the headset mikes worn by the singers. That method or singing along with a pre-recorded version is the likely method used to balance the first soloist's voice with the entire choir in the food court.