Matthew 15:15 – 20

15 Then Peter answered and said to Him, “Explain this parable to us.”

16 So Jesus said, “Are you also still without understanding?

17 Do you not yet understand that whatever enters the mouth goes into the stomach and is eliminated?

18 But those things which proceed out of the mouth come from the heart, and they defile a man.

19 For out of the heart proceed evil thoughts, murders, adulteries, fornications, thefts, false witness, blasphemies.

20 These are the things which defile a man, but to eat with unwashed hands does not defile a man.”

The lesson about the washing and eating was not an actual parable about the kingdom, but it was somewhat indirect and figurative in language so the disciples were a little confused and wanted an explanation.

Jesus sounds as if He is surprised at the lack of understanding shown by His disciples, but in reality He was not, He said this as a mild rebuke for their slowness of thinking through the words He had spoken.

Jesus is discussing dirt and not disease, the dirt and filth of eating with dirty hands is processed by the digestive organs and then eliminated through the intestines and passed out as waste products.

But the things which come out of the mouth are first thoughts which originate in the mind, if they are evil it indicates an impure and defiled heart.

The heart has been defined as the area of the human soul which thinks and has control of the moral character of an individual. It is why the things mentioned in this verse are considered as products of the heart.

These things mentioned as products of the heart such as lying, theft, unfaithfulness, and murder cannot be from a pure individual but show the person has a filthy or defiled heart, they do not come from the outer and is eaten by the mouth after been given by the hands to the mouth.

The evil produced by a human comes from the guilty heart not dirty hands.