What are the things that defile a man in Mark 7:15?

After one of His confrontations with the Pharisees and teachers of the law, Jesus gathered the people and taught them a needed lesson: “Hear Me, everyone, and understand,” He said. “There is nothing that enters a man from outside which can defile him; but the things which come out of him, those are the things that defile a man” (Mark 7:14–15, NKJV).

The defilement that Jesus spoke of was an “uncleanness” that makes a person unacceptable to God. That was the issue at hand and was, in fact, what Jesus and the Pharisees had just argued about. It all started when “the Pharisees and some of the teachers of the law who had come from Jerusalem gathered around Jesus and saw some of his disciples eating food with hands that were defiled, that is, unwashed” (Mark 7:1–2). “Defiled” hands would lead to a “defiled” spirit, according to the Pharisees, who viewed the traditional rituals as necessary to maintain a right standing with God.

Mark explains the Pharisees’ traditions for his readers: “The Pharisees and all the Jews do not eat unless they give their hands a ceremonial washing, holding to the tradition of the elders. When they come from the marketplace they do not eat unless they wash. And they observe many other traditions, such as the washing of cups, pitchers and kettles” (Mark 7:3–4). It’s important to note here that the Pharisees’ rule was not based on Scripture but on “the tradition of the elders.” In other words, the handwashing was a manmade rule, not God’s rule.

Jesus’ critics pressed the issue, demanding an answer: “So the Pharisees and teachers of the law asked Jesus, ‘Why don’t your disciples live according to the tradition of the elders instead of eating their food with defiled hands?’” (Mark 7:5).

Jesus’ answer was to call out their hypocrisy. Quoting Isaiah, Jesus told them they only paid lip-service to God even as their hearts were far from Him (Mark 7:6–7; cf. Isaiah 29:13). Jesus summed up their error, saying, “You have let go of the commands of God and are holding on to human traditions” (Mark 7:8). And He gave a concrete example of how they ignored God’s commandments in favor of their own traditions (verses 9–12). The tragic result of their insistence on tradition is that they “nullify the word of God” (Mark 7:13).

After His rebuke of the Pharisees, “Jesus called the crowd to him and said, ‘Listen to me, everyone, and understand this. Nothing outside a person can defile them by going into them. Rather, it is what comes out of a person that defiles them’” (Mark 7:14–15). The point is that spiritual defilement does not come through what we ingest—food or the manner of eating it does not affect the spirit. Spiritual defilement comes from within.

Later, the disciples ask Jesus what He meant, and He explains it further to them:

What is it that defiles a man and makes him spiritually unclean? Sin. Jesus’ list includes “evil thoughts, sexual immorality, theft, murder, adultery, greed, wickedness, deceit, lustful desires, envy, slander, pride, and foolishness” (Mark 7:21–22, NLT).

Sin begins in the heart, and sin defiles. That’s why the Bible places such an emphasis on the heart: “Above all else, guard your heart, for everything you do flows from it” (Proverbs 4:23).