With an MA in biblical studies from Dallas Theological Seminary, I can speak on a variety of biblical or theological themes. Please see my blog for sample speaking topics and audio/video. I am experienced with teaching adult Bible classes and "pulpit supply" - substitute preaching for Sunday church services. I'd be pleased to be a guest speaker for your event, whether it is a formal or informal one.
One interesting presentation I can offer is the Old Testament robes of the high priest. I possess the outfit, and place each piece on a model and give it New Testament application. Jesus is our great high priest. The gospel is presented clearly. It could "stand alone" or blend with a group studying Hebrews or the Pentateuch.
I am also a writer, and the author of a Christian non-fiction book entitled: Positively Powerless, How a Forgotten Movement Undermined Christianity.