What does it mean that “as a man thinks, so is he” in Proverbs 23:7?

TL;DR:

Proverbs 23:7 shows us that sometimes people do not mean what they say. We need to be discerning and respond appropriately when someone’s actions don’t match their words but rather convey what is really in their heart.

what does the bible say?

The phrase "as a man thinks, so is he" comes from the New King James version of Proverbs 23, a chapter providing advice for how to handle oneself in various situations. Proverbs 23:6–8 gives the example of a miser who offers a guest food, but in his heart, resents doing so. The cultural context of the time was to offer sustenance to visitors, which requires generosity. Proverbs 23:6 warns against taking food from a stingy host who invites you to eat but who does not really mean it. The host’s ungenerous attitude in providing it should cause us to avoid taking his food altogether. The larger lesson here is that we need to be discerning about what a person says and does. We do not need to question their motives, but we need to be discerning and respond appropriately when someone’s heart does not match their actions or words.

from the old testament

In Psalm 55:21, David laments a friend’s betrayal, commenting that “His speech was smooth as butter, / yet war was in his heart; / his words were softer than oil, / yet they were drawn swords.” Though the context differs from Proverbs 23:7, the same dichotomy between words and one’s heart is highlighted.
The difference between what words express and what the heart feels is further presented in Proverbs 26:24–25. These verses discuss the same type of deceit by someone who “hates” but “disguises himself with his lips / and harbors deceit in his heart.” The writer advises readers to “believe him not” although “he speaks graciously” (Proverbs 26:25).
The prophet Jeremiah observed such deceitfulness about Judah as they had abandoned God. From the rulers to the general populace, the people were deceitful: “Their tongue is a deadly arrow; it speaks deceitfully; with his mouth each speaks peace to his neighbor, but in his heart he plans an ambush for him” (Jeremiah 9:8).

from the new testament

In speaking of false prophets, Jesus expressed the difference between outward appearance and the heart: “On that day many will say to me, ‘Lord, Lord, did we not prophesy in your name, and cast out demons in your name, and do many mighty works in your name?’ And then will I declare to them, ‘I never knew you; depart from me, you workers of lawlessness’” (Matthew 7:22–23). Many who seem to be Christ’s followers do not really know Christ in their heart.
In Matthew 15:7–9, Jesus quotes the prophet Isaiah when speaking to the scribes and Pharisees: “Well did Isaiah prophesy of you, when he said: ‘This people honors me with their lips, but their heart is far from me; in vain do they worship me, teaching as doctrine the commandments of men.’” Jesus said this in the context of the scribes and Pharisees chastising His disciples for not following their own hand cleansing rituals before eating. Our Lord reprimands the scribes and Pharisees for ignoring the foundation of the Law–mercy and kindness—and focusing on burdensome rules they had created. Jesus exposed their true heart.
In that same chapter, Jesus notes the wickedness of the heart: “For out of the heart come evil thoughts, murder, adultery, sexual immorality, theft, false witness, slander. These are what defile a person. But to eat with unwashed hands does not defile anyone” (Matthew 15:19–20). This shows that what is in the heart will be reflected in one’s actions. Our actions are the test of what is in our hearts, just as the actions of the stingy host revealed a lack of generosity, despite his words.

implications for today

Proverbs 23:7 warns against accepting hospitality from a begrudging host. If you must partake, do so sparingly. Even though there may be the appearance of generosity, "his heart is not with you” (Proverbs 23:7). The food and conversation will not satisfy because it was not shared in genuine goodwill and generosity. On a broader level, this proverb instructs us of the deceit of humankind. People’s words do not always reflect true feelings. We should be alert to this disparity and ask the Lord for wisdom in such situations (James 1:5). The phrase "as a man thinks in his heart, so is he" is sometimes taken out of context and used in a motivational sense to get people to "think" themselves into improved life situations (i.e., those who believe thinking they’re successful will make them successful). That interpretation ignores the context of the proverb and misapplies it. Rather, the proverb warns that a person's actions are not always indicative of his true heart. "As a man thinks, so is he" means that who a person really is, is determined by their heart.

understand

A person’s true nature is revealed by their heart.
We are called to watch for discrepancies between a person’s actions and true intentions.
A person’s actions reveal their heart.

reflect

What is the connection between your actions and words and your heart, feelings, and/or intentions?
What should you do when your outward behavior does not align with your inner thoughts?
Have you encountered situations where someone’s actions didn’t match their words? How did you respond? What did you learn from those experiences?

engage

How do the examples of deceit in the Old Testament (e.g., Psalm 55:21; Proverbs 26:24–25) help us understand the implications of Proverbs 23:7 for recognizing false intentions?
How do Jesus’ teachings about false prophets and the discrepancies between outward appearances and the heart (e.g., Matthew 7:22–23; 15:8–20) expand our understanding of Proverbs 23:7?
What practical steps can we take to discern when someone’s actions are not aligned with their true intentions without becoming judgmental of their motives? How can we respond in a way that is both wise and compassionate?