I have lost the toolbar, action bar, and/or menu bar in PocketBible.

A double-tap on the screen will show/hide the action bar and toolbars. You have probably accidentally hidden them. Double-tap the screen to show them again.

If you don't like the double-tap option, turn it off under Settings > Control Settings. Uncheck the first two items and a double-tap will not show/hide your menus.