Cleaning with Hyssop

Cleanse me with hyssop, and I will be clean; wash me, and I will be whiter than snow. - Psalm 51:7

I have read that the reference to hyssop in verse 7 most likely referred to a plant named ezov, but has been interpreted to be hyssop.  This is significant because of its symbology and the Eastern style of teaching is with such techniques.  Ezov is readily found in Israel and it is generally thought that it was also used by the Jews to put the unblemished lamb's blood on the door mantels in Egypt so God would spare their first born (the Passover).  The blood of the spotless lambs preventing the death of Jews is another way that God was preparing the Jews to understand that there would have to be a perfect life to be shed and His blood would prevent the eternal death of all.  Here the writer calls out for God to cleanse him with it from his sin and only then would he be clean.  He seems to be asking God to use the same power He used to keep the Hebrew children alive from the death angel to remove his sin.  This is a remarkable insight having been written before Jesus came.  He understands that God has to do the cleaning; God has to bear the burden of the sin; God has to wipe the sin clean.  

Now let me enlighten this text and concept for this highly advanced civilization that I am a part of: simply put, two muddy people in a mud hole can't clean themselves or one another.  Someone not in the mud hole has to clean them.  I heard a preacher exclaim, "You can go to God smelling like a pig!"  Truth is, we have to go to God smelling like a pig and covered in mud.  We can't wipe it off and neither can anyone else.  Only He can clean us.