Charles Ellicott Commentary Proverbs 26:7

"The legs of the lame hang loose: So is a parable in the mouth of fools." — Proverbs 26:7 (ASV)

The legs of the lame are not equal.— Better, perhaps. The legs hang down from a lame man, and so is a parable (useless) in the mouth of fools; they can make no more use of it for the guidance of themselves or others, than can a lame man use his legs. (Compare to Luke 8:10.)