A Serious Man ending explained

What happens

At Danny's bar mitzvah, Marshak returns the boy's confiscated radio with cryptic words. Larry then gets an urgent call from his doctor, and Danny sees a tornado bearing down on the school. Cut to black. Nothing is explained.

The last image

A tornado is approaching the school, and the screen cuts to black before it arrives.

Three readings

1 · Judgment arrivesLarry changed the grade and the storm follows, so the cosmos has finally answered him with punishment.

2 · Pure chanceThe doctor's call and the tornado are just more random events, with no meaning behind them.

3 · Blessing or curseLike the prologue's visitor, the storm can't be judged, and certainty either way is the danger.

What it says

The ending denies Larry, and you, the answer he has chased all film. Good behaviour guarantees nothing, and no authority can explain why. It closes on the question itself, which is the film's point.