This song (aside from the singing) is made 100% from in-game audio. There are no additional instruments, samples, etc - it's all built from Warframe sounds.

LYRICS:
Believers! Listen!
Don't try to tell me that the power of belief is broken
just look at what the void has done in my life
Don't say that you expected more return from your investment
You simply didn't have the faith it required
Don't try to say I'm just another dealer of redemption
I've got the only kind of faith you can buy
It doesn't matter what the circumstance of your belief is
just give me credits till you feel that it'll be alright

Gather your funds and invest you profit seekers!
The void is eager!
To make you a believer!
Poverty comes as a cure it's illuminating
The void is waiting!
So give us all your savings!

Scoundrels! Heretics! Believers!
Lovers of Profit! Devout followers of the void!
Listen, do you crave redemption?
The void be the word, and the word be profit

Do you want what I've received?
Do you want it for yourself?
Then, let your credits be the seeds of your prosperity
The void be the word, and the word be profit

I used to be a wretched crewman working for my credits
Until I learned what life was really about
But now I'm living on the seeds of your donations because
My faith was strong enough to turn it around
Don't try to tell me bout the vagaries of growth and profit
The void has given us a simple design
You put together all the earnings you've been saving up and
You call me up so we can kiss every one of them goodbye!

Gather your funds and invest you profit seekers!
The void is eager!
To make you a believer!
Poverty comes as a cure it's illuminating
The void is waiting!
So give us all your savings!

Come and receive of the void this faithful spleador
The void is blessing!
It's richness manifesting!
Give of yourself to the void you meek and meager
The void is profit!
So come make a deposit!

Scoundrels! Heretics! Believers!
Lovers of Profit! Devout followers of the void!
Listen, do you crave redemption?
The void be the word, and the word be profit

Do you want what I've received?
Do you want it for yourself?
Then, let your credits be the seeds of your prosperity
The void be the word, and the word be profit

Have you given your offering today?