Yes, that is true.  St. Paul does use those words.  But, the crux of the matter for me revolves around the meaning of "unworthily", which, St. Paul does not define.  Jesus gives us a very clear picture of unworthiness when he speaks of the Pharisee vocally congratulating himself on his self perceived "worthiness" versus the humble sinner who knows his "unworthiness".  Might St. Paul's words be a reflection of Jesus teaching?  Isn't it just possible that St. Paul is in fact reminding us that the truly "unworthy" are those that are self justified in their false sense of piety?  Which leads me back to my initial point.  Maybe if we have a Eucharistic celebration where all are humbly invited forward to participate in communion with Jesus, starting with those that feel and know they are the most broken, we would be more faithful to the radical teaching of Jesus that all are welcome at his table.