Iterate through RichTextBox in a static thread?

so as the title says.. i have a thread which has to be static

 

Thread runThread = new Thread(running);

static void running()   // this has to be static else i get an error on "new Thread(running)"
{

//in here i want to iterate through each line in RichTextBox but i can't because RichTextBox isn't static...

}

 

btw im new to c# so dont blame me if i did a big mistake or something ... just want to know the problem and how i could do it even better so i can improve.

thanks for any help :)

 

Or maybe you know how to create a non static thread... idk really :/