Translation
They have tails and stingers like scorpions,
Go to footnote numberand in their tails they had the power to inflict injury on men for five months.
Go to footnote numberParaphrase
They could cause pain in numerous and unexpected ways,
and that pain is the most intense pain known to man from an outside source, but it was restricted to a limited amount of time.
Footnotes
1: “tails and stingers like scorpions”
There are two things being communicated here. 1) the tail was not a very desirable part of most animals for it often got covered with manure. 2) It is also at the opposite end of the animal from the head. In this usage it shows that these agents of evil are able to cause harm from any direction, whether attacking us, or even while retreating, and they can harm us even with the most insignificant and least expected part of them. The point is that Satan’s minions have many ways they can cause us harm.
2: “five months”
Five stands in contrast to 10 which is the symbol for completeness in a structural or legal sense. Satan can inflict suffering on men but only for a limited time, and he is not in control of life or death. This is one of many ways that Revelation shows that something will be limited, or cut short.