What does the song Sulfur mean by slipknot?

What does Sulfur mean because Slipknot’s song Sulfur tells me something about being hurt physically and mentally,read yourself:

My guilt and my shame Always sell me short always feel the same And my face and my soul Always wear me thin always under control But the longest hours you’ll have in your life Are the ones you sit through to know if you’re right So I’ll wait but I’ll pray that I’m wrong Because I think I know what’s going on

So let me get this straight the only will is my own I do whatever I want and stay alone All my decisions make it untouchable and tainted I’m gonna suffer for the rest of my life But I will always find a way to survive I’m not a failure but I know what It’s like I can take it or leave it or die

STAY…You don’t always know where you stand ‘Till you know that you won’t run away Theres something inside me that feels Like breathing in sulfur…

My life is undone I’m a sinner to most but a sage to some And my Gods are untrue I’m probably wrong but I’m better than you And the longest hours I had in my life Were the ones I went through to know I was right So I’m safe but I’m a little outside I’m gonna laugh when I’m buried alive

STAY…You don’t always know where you stand ‘Till you know that you won’t run away Theres something inside me that feels Like breathing in sulfur..