tails: As the scorpion goes along softly, but strikes with its tail, so the pernicious craftiness of the wicked seems in appearance gentle and harmless, but in that it secretly destroys as in some hidden manner, it brings with it death.
And their power was to hurt men five months. The duration of their power is here limited, but we dare not venture to explain what is meant by the dark expression, five months; time to come must clear up the difficulty. (Haydock)