Jesus was dealing with people who were trying to avoid contaminating themselves by what they were eating, i.e., what they were taking in. He concludes His speech on this subject by saying, “All these evil things come from within, and they defile a person.” The human heart is desperately wicked and we are all more capable of evil than we think. It seems to me that Jesus is saying that when we give expression to these inner inclinations, then we defile our person, making ourselves unclean. Be careful what you let your mind think, what you let your heart yield to, what you let your eyes see, what you let your hands do, and what you let your mouth say.
18 And he said to them, “Then are you also without understanding? Do you not see that whatever goes into a person from outside cannot defile him, 19 since it enters not his heart but his stomach, and is expelled?” (Thus he declared all foods clean.) 20 And he said, “What comes out of a person is what defiles him. 21 For from within, out of the heart of man, come evil thoughts, sexual immorality, theft, murder, adultery, 22 coveting, wickedness, deceit, sensuality, envy, slander, pride, foolishness. 23 All these evil things come from within, and they defile a person.” (Mark 7:18–23 ESV)
