Andrew of Caesarea
"But that they should receive torment for five months" means that sinners will be tormented fiercely and grievously only for a certain appointed time, and afterward more lightly, yet eternally.
We think the five months of torments indicate their short duration. For the Lord says, "Unless those days were shortened, no flesh would be saved" (Mt 24:22).
Or they indicate a certain fivefold time corresponding to the five external senses, through which sin acts in man. Or they indicate, in general, an appointed time known only to God.