Cleanse first that which is within the cup and the platter - Let them be filled with the fruits of honest industry, and then the outside and the inside will be really “clean.” By this allusion to the cup and platter he taught them that it was necessary to cleanse the heart first, that the external conduct might be really pure and holy.
Related Commentaries of Matthew 23:26
Matthew 23:26
26 Thou blind Pharisee, cleanse first that which is within the cup and platter, that the outside of them may be clean also.