Wide angle for concert

I am the head of photography for a big(~1000-2000) church concert...I have been to the church once and know it is way too big for a flash. I am thinking of buying or renting a wide angle prime lens. I just got a sigma 50 1.4, but i feel that may not be wide enough. Would the 35 1.4 sig do the job? Or should i look at renting a 24L?(probably not that crazy about renting a very expensive lens cause ill forget i cant keep it)

35 is wide enough for most concerts, I'd think.

Go to the church with your 50 and see if it will do the job or not. The church is big but how big is the stage or the performing group.

-Points to wish list.-