Practicing Bach for Sunday

We (not the squirrel in my pocket, but my fellow choir members and I) are doing Bach's cantata, "Gottes Zeit ist die allerbeste Zeit" (BWV 106) on Sunday at church, and I've been practicing it in preparation for our final rehearsal, which is tomorrow morning. I am blown away by the music, especially the part where the soprano sings "Ja, ja, Herr Jesu, komm!" while one section after another sings "Es ist die alte Bund: Mensch, du musst sterben".

I'm going to ask if I can leave a laptop in the choir loft during the service, with some special "rabbit ears" I just fashioned.