By JIM NICHOLS

You probably have several of these in your purse or your pants pocket. They are small metal pieces with notches cut out in some pattern along one side. There is a hole in the wider end of the piece, and you probably have them connected by some type of attachment. These pieces can be inserted into the lock on a door, turned, and, if the notches line up correctly, the lock can be undone. They are, of course, keys.

It goes without saying that the match between key and lock is a specific one. One of my teenage part time jobs at a drugstore involved my using a grinding machine to create copies of keys customers brought in. It needed to be done accurately; the pattern on the master key had to match the copy key. After I cut what I thought was the correct pattern, I would use a metal file to smooth out the curves and notches so, hopefully, the new copy key would fit easily into the lock. It is obvious when the key and lock are not a match.

There is a scientific illustration that uses this concept. You might understand that, generally, chemical molecules are too small to be seen easily, even with extremely high magnification. It is also clear, however, that in many cases molecules interact with one another in chemical reactions. To react they must bump into each other—that is, physically contact one another momentarily. 

This physical contact cannot be haphazard, however. Correct interaction between the molecules depends on the shapes of the molecules and whether they “fit” together appropriately. In many biological cases, there are special “helper” molecules that aid in establishing the “match” between the two potentially reacting molecules. These “helper” molecules (called enzymes) have a specific shape also that is critical in achieving the appropriate combination.

All this consideration of “fit” and “match” closely resembles the way a key and lock operate. In fact, a science book would describe this as the “lock and key” explanation for the appropriate chemical reaction.

The clearest criticism of this lock and key model is that reality seems to be more flexible than this rigid (“do the notches match exactly?”) situation. A helpful modification of the lock and key concept is referred to as the “induced fit” model. This suggests that the reactant molecules are a bit pliable and that they mold themselves somewhat so that they do, in fact, match up sufficiently. The function can be performed even though, at first glance, the molecules do not seem to have an exact fit together.

A non-chemical illustration is the way in which a glove molds itself to a hand inserted into it. An empty glove looks like a hand, but it is non-functional until it is filled. At that point, the hand and glove are a single unit.

The parallel to the Christian community is not difficult to see. You and I are both participants in churches, book, and prayer groups, even friendships whose function depends on a religious type of “induced fit.” That is, we are each unique in the gifts God has given us. A lock and key approach would require that the notches and other cuts in me exactly match those in you; if that does not happen, we will not be able to function in communion. We all know some believers who try to function in this rigid world, and we see its lack of success.

On the other hand, in my better moments I can see that who you are as God’s follower influences my ability to be a follower—and vice versa. I am not who I should be as God’s person unless I receive God’s influence through you. This is like a hand and glove—we would be hard-pressed to identify which is more important. This is the “induced fit” model in a spiritual setting.

One of the characteristics of the Christian life is that there is an individual level plus a community level. I have a personal relationship with God that exists in parallel to my functional role in the Christian community. Both are necessary.

Jim Nichols is a retired Abilene Christian University biology professor and current hospice chaplain