Last night DOB recoiled in horror when he noticed that the outside of the salad bowl was distinctly greasy feeling. (I'm definitely not the world's most skilled dishwasher, and plastic bowls tell all.) I apologized and tried to reassure him.
"I know the inside is clean, I just sometimes forget to get the outside clean, too."
"If you don't clean the outside, it's going to get the inside of another bowl dirty."
"I know. I guess it just goes to show that I'm not a Pharisee." (Referencing Matthew 23:25.)
On further examination of the passage, it even could be construed to offer divine endorsement of the idea that cleaning the inside is sufficient. But DOB assures me that it is not.