I guess I don't understand then... if you look at the template for the editor you are using, you'll see something like this for the editor textarea:
HTML Code:
<textarea name="message" id="{vb:raw editorid}_textarea" rows="10" cols="80" tabindex="1" dir="{vb:stylevar textdirection}">{vb:raw newpost.message}</textarea>
so, you'd set $newpost.message to be whatever text you have gotten from your query.