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The Mathematics Of Marriage

(A chapel talk given at Immanuel Lutheran High School, Mankato, Minn. Teacher Kevin Hulke is the Gospel messenger.)

People often have a hard time understanding what life is like after being married. Obviously for young adults the understanding is even harder to come by. A careful study of what Scripture says about marriage will help you see your future, and also help you see ways to improve the friendships you now have.

Being a math teacher, I see many applications to mathematics in things that don’t even involve numbers. It is hoped that the mathematics of marriage will help you to better remember what God has to say about marriage.

Subtraction Of Self

God saw the need for marriage from the beginning. When He saw Adam, He said: “It is not good that man should be alone; I will make him a helper comparable to him” (Gen. 2:18). After that Adam, too, having named all the animals, could see that none of them could fill his “aloneness.” It is after the creation of Eve that he said: “Therefore a man shall leave his father and mother and be joined to his wife, and they shall become one flesh.”

Even in first grade you knew that to have two things become one you have to subtract one. When we think about what to subtract, a perfectly obvious subtraction would be to subtract yourself. When you get married, you have to quit thinking about what I want, and start thing about what we want.

This is not an easy thing to do, as any married person will tell you. But when it works, the marriage is blessed. Some of this subtraction is also good in developing any good friendship. When you are with your friends, ask what they would like to do. This is one of the things that the book “How to Win Friends and Influence People” recommends.

Addition Of God’s Gifts

With such subtraction of self come some additions. God tells us that when we consider others more highly than ourselves, we get His rewards. In marriage these rewards are easy to see. The first is that when you give gifts or help out, you will see the sparkle in your spouse’s eyes. After all, how many people have others doing things for them?

For husbands God promises answers to prayer. As Luther says in the Table of Duties: “Likewise, you husbands, dwell with your wives with understanding, giving honor to the wife, as to the weaker vessel, and as being heirs together of the grace of life, that your prayers be not hindered” (1 Pet. 3:7). That little phrase, “weaker vessel,” means something like fine china instead of every day dishes, or something not to be abused. For wives, their addition is being called the daughters of Sarah, as Luther quotes from the Bible: “Wives, submit to your own husband, as to the Lord, just as Sarah obeyed Abraham, calling him lord, whose daughters you are if you do good and are not afraid with any terror.”

In both of these additions the words are only meant for that person. Husbands, don’t tell the wives they must submit! Wives, don’t tell the husbands to honor!


When you multiply percents, you know that the answers are different than you expect. A person may say they want the marriage to be a 50/50 split. But when you multiply 50% by 50% you get 25%, or only a fourth of a marriage. To get a full marriage each person has to give 100%.

Wouldn’t you be skeptical about buying something for only 25% of its value? What is it worth? Is something broken? These are the questions I would be asking about such a “bargain.” So when you give 100% of your effort, you get 100% of a marriage. Anything less than your all is not enough.

In your friendships, do the same thing. Give the friendship your all, and the friendship will be full.

Multiplication comes in another way also. In Genesis God says: “Be fruitful and multiply; fill the earth and subdue it.” In our day many people, even Christians, are content to “be fruitless and add.” They have few or no children. When they willfully do so, they only withhold blessings from themselves.

If Christians are not multiplying, then there are fewer Christians. If the pagan world multiplies and we add, then they will strengthen the devil’s hold on the earth. As you and your spouse discuss the number of children you are going to have, keep God’s command and promise in mind, because He does promise: “Behold, children are a heritage from the Lord, the fruit of the womb is His reward” (Ps. 127:3).

No Division

A discussion about the mathematics of marriage would not be complete without talking about division. In marriage there is none. In Matthew 19 God says: “What God has joined together, let not man separate (divide).”

If you concern yourself with subtracting yourself from the marriage, with adding God’s blessings, then you won’t have to worry about dividing. If you pay attention to the way the multiplication of marriage works, then division is no longer a concern.

As Luther says:

Let each his lesson learn with care. And all the household well shall fare.

–Teacher Kevin Hulke