Simon Peter saith unto him, Lord, not my feet only, but also my hands and my head. Lord, not my feet only, etc. - It appears that Peter entered into our Lord's meaning, and saw that this was emblematical of a spiritual cleansing: therefore he wishes to be completely washed.
Related Commentaries of John 13:9
John 13:9
9 Simon Peter saith unto him, Lord, not my feet only, but also my hands and my head.