Actually, it's Elly criticizing John's lack of fashion sense.
Panel 1: We start with her yelling "JOHN!! YOU'RE NOT GOING OUT DRESSED LIKE THAT!!"
Panel 2: This is because, as she explains in a disgusted tone of voice, he's wearing an orange and blue plaid shirt and green trousers with a houndstooth pattern. Her revulsion is such that she yells AAAAACK as if she were Cathy-must-die.
Panel 3: With her palms outstretched, she asks him what the neighbors are supposed to think.
Panel 4: He replies that they'll think he's a man fixing a fence. That's because he's a man fixing a fence and thus joins most of humanity in not caring that he looks like a member of Possum Lodge.
Summary: This leads directly to a strip that has him inform him that if he changes in the slightest, he cannot be happy in the least so she should quit trying to reform him. That's because the poor fool doesn't realize that her yelling will erode away at his personality; eventually, he will hide in his toolshed and play with trains to avoid her wrath. Said wrath would be invoked by his reminding her that she isn't exactly the snappiest dresser herself. The reason for all this, is of course, because Lynn is mad at Rod and will do anything to make us as angry at him as she is.