In the appendix to Sam Crabtree’s Practicing Affirmation he reproduces a helpful grid:

(Beevers’ Grid copyright 1986 by Ernest Beevers. Used by permission.)

Crabtree explains (pp. 161-162) how this can be used to help determine when to correct someone and when to let it go.

The vertical axis indicates the importance of the issue being considered. The bottom reflects issues of low importance such as trying to resolve whether President George Washington ever wore socks that didn’t match. It is an issue of virtually no consequence. Moving up the axis, toward the top we reach issues that are important, issues that have life-and-death significance, perhaps for a great many people. Between the top and the bottom is an array of issues and their relative importance or unimportance.

The horizontal axis indicates my certainty that I am right. Toward the left are issues about which I don’t have the foggiest clue (what is the name of the dog owned by the bit player in that 1938 movie that no one saw?). Toward the right are issues about which I am sure that I’m sure before God, the angels, and all the witnesses that could be summoned that I am right. Most people find that there are surprisingly few of these issues.

Any issue of controversy can be plotted on this matrix.

The lower-left quadrant contains issues that meet two simultaneous criteria: (1) they are of low importance, and (2) I do not know much about them. For example: how many angels can dance on the head of a pin? Who knows? And who cares? Here’s the point: it wouldn’t be worth consuming relational energy to argue about this issue or to correct someone else’s viewpoint.

The upper-left quadrant contains issues that meet two simultaneous criteria: (1) they are of high importance, but (2) I still don’t know with certainty what the truth is. For example: When is Jesus returning? That is of crucial and everlasting importance to every person who lives or ever has lived! And yet I don’t know when he’s coming back. One of the things about which I’m certain is that I am not certain about exactly when he’s returning. The point is: arguing about it or correcting others is not worth the relational energy it would consume.

The lower-right quadrant contains issues about which (1) I’m certain I’m right, but (2) they are of low importance. For example: how many knots are in the log I am now looking at? I know the answer, but why make an issue of it?

And now we arrive at the main observation to be derived from Beever’s Grid. The upper-right quadrant simultaneously contains the issues (1) that are important, and (2) for which there is virtually no possibility that I will be shown to be mistaken.

And here’s the point: reserve your conflict, your arguments, and your persistent corrections to that quadrant.

Here’s its corollary: keep that region small. The fruitfulness of correction tends to come from a smaller region than we assume. We default to making that region larger than is fruitful. We wear people out by putting more issues in the upper-right quadrant than belong there.

(Emphasis mine.)