The wicked are overthrown, and are not; or, overthrow the wicked, and they shall be no more. The verb is in the infinitive, and may be rendered either way; but the notion is scarcely of an overthrow.
The Vulgate has, verte impios; i.e. change them a little from their previous state, let them suffer a blow from any cause or of any degree, and they succumb, they have no power of resistance. What the stroke is, or whence it comes, is not expressed; it may be the just judgment of God—temptation, trouble, sickness—but whatever it is, they cannot withstand it as the righteous do (see Proverbs 11:7).
Some commentators see in the phrase the idea of suddenness, "While they turn themselves round, they are no more" (Proverbs 10:25; Job 20:5). Septuagint, "Wheresoever the wicked turn, he is destroyed."
The house of the righteous, being founded on a secure foundation, shall stand (Matthew 7:24, etc.).