And he saith unto them
 With some warmth of spirit and resentment, at their stupidity: 
 are ye so without understanding also?
 As well as others, and to such a degree; and "yet", as Matthew expresses it, ( Matthew 15:16 ) , so wretchedly stupid, and so long, and as much, as others: 
 do ye not perceive?
 common sense will tell you, 
 that whatsoever thing from, without entereth into the man, it cannot
 defile him; (See Gill on Matthew 15:16).