What Grudges Do to the Body

In 2001, psychologist Dr. Charlotte vanOyen Witvliet at Hope College conducted a study that made the invisible visible. She asked volunteers to recall someone who had deeply wronged them. When participants mentally rehearsed the grudge — replaying the offense, nursing the resentment — their heart rates climbed, blood pressure spiked, stress hormones flooded their systems, and their facial muscles tensed. Their bodies responded as though the original threat were happening again, right there in the laboratory.

Then she asked them to imagine extending empathy and forgiveness toward that same person. The monitors told a different story: heart rates slowed, muscles relaxed, stress responses receded. The body began to settle — not because the offense was erased, but because the grip of bitterness was released.

Here is what medicine confirms and Scripture has always known: unforgiveness is not a passive state. It is an active poison. Every time we rehearse the wrong done to us, our bodies re-experience the wound as though it were fresh. Bitterness does not punish the offender. It punishes the one who carries it.

Paul wrote to the Ephesians, "Get rid of all bitterness, rage and anger... Be kind and compassionate to one another, forgiving each other, just as in Christ God forgave you" (Ephesians 4:31-32). That is not merely spiritual counsel. It is a prescription for healing.

Forgiveness does not mean the wound never happened. It means you stop reopening it. And when you finally let go, something remarkable occurs — your whole body breathes again.