Jesus pointed the disciples to something everyone knows from daily life. Food goes into the stomach and passes out of the body; Mark adds that it "entereth not into his heart" (Mark 7:19). Barnes sums up the meaning: "The food which is eaten does not affect the mind, and therefore cannot pollute it." Gill says "no moral pollution can be contracted by eating any sort of food." By asking "Do not ye yet understand," Jesus invited them to reason it through for themselves before He gave the rest of the answer.

Jesus completed the thought Himself: "But those things which proceed out of the mouth come forth from the heart; and they defile the man" (Matthew 15:18). He named what comes from the heart: "evil thoughts, murders, adulteries, fornications, thefts, false witness, blasphemies" (Matthew 15:19). Then He returned to the Pharisees' original complaint: "These are the things which defile a man: but to eat with unwashen hands defileth not a man" (Matthew 15:20).

The KJV word "draught" is old English for a privy or latrine. It translates the Greek aphedrōn, which Thayer defines as a privy or sink. It appears only here and in the parallel, Mark 7:19.

Mark's account ends the same sentence with the words "purging all meats" (Mark 7:19). The ESV renders Mark's point as "(Thus he declared all foods clean.)" Matthew does not include that comment, but both Gospels record Jesus making the same contrast between the stomach and the heart.

Jesus moved the question of cleanness from the hands to the heart. The Pharisees were careful about what touched their food, but sin does not come in through the mouth; it comes out from within. Matthew Henry writes, "It is the heart that is desperately wicked," quoting Jeremiah 17:9, "for there is no sin in word or deed, which was not first in the heart."

This shows how God sees people. He looks past outward rituals to the source of what we say and do. That is humbling, because no washing can reach the heart, and it is also clarifying: real cleansing has to happen where the real problem is.