As the whirlwind passeth, so is the wicked no more: but the righteous is an everlasting foundation.
As the whirlwind passeth, so (is) the wicked no (more) - as rapidly as the whirlwind passes. No wind is more violent or less lasting. So the wicked, the more violent and mischievous they are, the more quickly they fall (cf. Proverbs 1:27).
But the righteous (is) an everlasting foundation. He becomes like the foundation on which he rests, the everlasting God (Matthew 7:24-25; Psalms 15:5, end). He is solid, immovable, always consistent, and his happiness well-founded and eternal (Maimonides). The righteous is the foundation of the world; the world stands for the sake of the righteous.