As a snail which melteth - The Chaldee reads the verse thus: "They shall melt away in their sins as water flows off; as the creeping snail that smears its track; as the untimely birth and the blind mole, which do not see the sun."
The original word שבלול shablul, a snail, is either from שביל shebil, a path, because it leaves a shining path after it by emitting a portion of slime, and thus glaring the ground; and therefore might be emphatically called the pathmaker; or from ישב yashab to dwell, ב be, in, לול lul, a winding or spiral shell, which is well known to be its house, and which it always inhabits; for when it is not coiled up within this shell, it carries it with it wheresoever it goes. See Bochart. These figures need no farther explanation.
As a snail which melteth, let every one of them pass away - Or rather, As the snail which melteth as it goes; that is, which leaves a slimy trail as it moves along, and thus melts away the more as it advances, until at length it dies. Gesenius, Lexicon. The allusion is to what seems to occur to the snail; it seems to melt or to be dissolved as it moves along; or seems to leave a part of itself in the slime which flows from it.
Like the untimely birth of a woman - The Hebrew word means literally “that which falls from a woman;” and hence, the word is used to denote an abortion. The prayer is, that they might utterly pass away; that they might become like those who never had real life; that their power might wholly disappear.
That they may not see the sun - May not be among the living. Compare the notes at Job 3:16.