dismiss demon god

I would actually say that with the exception of a few Asian religions demons aren't gods. Do not dismiss, that is disrespectful and suggests superiority. Simply thank them for any assistance and let them be on their way. If they don't leave you obviously have some unfinished business to tend to before they part which then you can inquire as to what that is and deal with it.

be gone demons send your souls back to hell can i use this

Lucifer is not a demon. He is a fallen angel, one who disobeyed God in the Christian religion by not bowing down to the humans God had created. In Christianity he is said to hate our guts, which I wouldn't find hard to believe. I talked to him however the other night, trying to offer some council since well... I love to help those in need. He just seems like a lost soul to me, but he does have a purpose in every matter. I believe that he tries to test us. So just let him be. Be prepared by equipping yourself with the right spiritual protection. Be respectful though, best not to tick off the supernatural.