Is it okay for Christians to participate in or celebrate Halloween?

You have to figure out where that line is for you and your loved ones. Objectively, there is nothing wrong with dressing up and becoming a character for an hour; that is called acting, and there is nothing wrong with acting. The question is whether we want our children acting out roles traditionally understood to be of an evil or devilish nature, and the answer there is no; that is where we draw the line, and always have. I once took my six-year-old son out dressed as a biblical angel with a sword, like the angel set with a flaming sword in the Garden of Eden, and a man at the door laughed because he could not see the connection between an angel and a sword. It is fine to pretend with costumes, as long as we portray decent characters and can come out of the fantasy; the danger is when people cannot come out of the surrealism they create. Remember that Halloween used to be 'Hallowed Eve,' the day before All Saints Day, tied to the dead rising from their graves to heaven, and the secular world has distorted it, just as it distorted Christmas by replacing Christ with Santa. So participate if you keep decent portrayals and break the mold of promoting things associated with evil.