The speaker describes a neighbour who seems tightly wound: fists closed, nothing in his hands but dirt under his nails. He tries to hold himself in, but his eyes give him away. The speaker names what lies underneath, loneliness, fear, confusion and repression, and imagines these rotting like fruit until they grow the mould of aggression.
The poem then turns to a careful moral balance. Everyone deserves some sympathy, the speaker says, but that sympathy shouldn't be taken as permission, perhaps meaning permission to cause harm. The short lines about September and apples that won't stay ripe forever read as a quiet warning: time is running out, and what is left to spoil may turn worse. The mood is uneasy and watchful. The speaker is compassionate but guarded, understanding the neighbour's pain without wanting to excuse what it might become.