What is it, most importantly, that causes relationships to be sustained over the long haul? In a word, it is forgiveness.

Why do I say that? First of all, no matter who you’re married to, they’re going to fail you, offend you, and misunderstand you. And you are going to sin against them and disappoint them. This is true in any kind of relationship, because we are sinful creatures. And what keeps that from destroying relationships is forgiveness.

In fact, in Proverbs 19:11 it says that it is a man’s glory to overlook a transgression. Never is a man more lofty or more noble than when he forgives.

Frankly, we live in a society that would not accept this. And consequently, relationships are flying apart all over the place. We live in a sad society on the road to total self-destruction, and one of the main contributors of that self-destruction is a disdain for forgiveness.

People are filled with bitterness, anger, hate, and vengeance toward others. They believe that retaliation is a virtue and that getting back is somehow right and healthy.

Such attitudes are approved in our culture on every front. They’re approved by counselors and psychologists, who tell us we need to vent. Such attitudes are exalted in the heroes of our culture, who have an “in your face” kind of mentality. People make heroes out of the vindictive — the Dirty Harrys, the Rambos, the Terminators, those types who find joy in killing for the sake of vengeance.

There are those in our society who go around killing people because they feel that they have been mistreated, and so they get their pound of flesh by random execution.

In fact, it’s often suggested that forgiveness is unhealthy. It’s sort of wimpy and cowardly. We’ve all been oppressed, abused, and victimized, and we aren’t about to forgive anybody.

But the price of vengeance is extremely high. The price of unforgiveness is really severe. Let me tell you some of the things that unforgiveness does.

First, unforgiveness imprisons people in the past. As long as you are unwilling to forgive offenders and their offenses, you are shackled to them both. The pain is there, and you’re picking at an open sore, keeping it from healing.

When you won’t forgive, you are sentencing yourself to go through life feeling as bad now as you did in the past when the offense was committed, with no end in sight. You choose to love hate and cultivate it through your life. Unforgiveness imprisons you in the pain of your past.

Second, unforgiveness inevitably produces deep bitterness. The Book of Hebrews calls it a root of bitterness — bitterness deep down, an infectious cancer in the heart. Such bitterness is malignant and devastating. It brings those malignant thoughts, those harassing memories that distort how you see life. Anger rages out of control, emotions become unbridled and unchecked, and you entertain desperate ideas for revenge. Every conversation becomes a forum for slandering the person you hate.

Unforgiveness is a very severe thing. It will shackle you to the pain of your past and it will provide for you a deep bitterness. On the other hand, forgiveness brings complete freedom from the past and from bitterness in the present.

When you study the Bible, there is a lot in it about forgiveness. In fact, there are 75 word pictures for “forgiveness” in the Bible. Let me give you just a few of them.

• To forgive is to turn the key, open the cell door and let the prisoner walk free.
• To forgive is to write in large letters across a debt, “NOTHING OWED.”
• To forgive is to pound the gavel in a courtroom and declare, “Not Guilty!”
• To forgive is to shoot an arrow so high and so far it can never be found again.
• To forgive is to take out the garbage and dispose of it once and for all, leaving the house fresh and clean.
• To forgive is to loose the anchor and set the ship free to sail.
• To forgive is to grant a full pardon to a condemned and sentenced criminal.
• To forgive is to loosen a stranglehold on a wrestling opponent.
• To forgive is to smash a clay pot into a thousand pieces so it could never be put back together again.

Those are just some of the word pictures in the Bible about forgiveness. Forgiveness is a marvelous, virtuous, liberating, loving attitude and act. It makes sense to forgive. It is healthy. It is wholesome. It is liberating. It is sensible. It relieves tension. It brings peace. It solicits love. And again I say, it is man at his noblest. It is his glory to overlook a transgression.

And I’ll tell you something. No relationship can survive the absence of forgiveness. If you don’t forgive continually, you will accumulate bitterness that will destroy any and every relationship.

This post is based on a sermon Dr. MacArthur preached in 1996, titled “The Key to Maintaining Family Unity.” In addition to serving as the pastor of Grace Community Church and the voice of Grace to You, Dr. MacArthur is the chancellor of The Master’s University in Santa Clarita, Calif. You can learn more about TMU at masters.edu.