Q&A: What Makes Ouija Boards Doors to Negative Energies?

Over the next 5 weeks, every Tuesday, I'll be featuring a question that I received via email, and my response. 

1. What makes Ouija boards doors to negative energies?  Ouija boards can open doors and bring positive spirits in, but it can also bring in nasty entities. Think of a Ouija board as being your front door of your home. You stand at the door and shout "Come on in!" and anyone and everyone can come in without you seeing them. Just as evil people would break into your home, you're inviting their ghosts in, too.

1a  Can protective words be said before using one regarding only letting positive energies to come through or something?   A user can offer prayers of protection around themselves, but again, it's like physical people coming into your house that you can't fight off all at once.