Albert Barnes Commentary Proverbs 18:1

"He that separateth himself seeketh [his own] desire, And rageth against all sound wisdom." — Proverbs 18:1 (ASV)

The text and the marginal readings indicate the two chief interpretations of this somewhat difficult verse. Other renderings are:

1. He who separates himself from others seeks his own desire, and rushes forward against all wise counsel: a warning against self-will and the self-assertion which exults in differing from the received customs and opinions of mankind.
2. He who separates himself (from the foolish, unlearned multitude) seeks his own desire (that which is worthy to be desired), and mingles himself with all wisdom. So the Jewish commentators generally.

Between (1) blaming and (2) commending the life of isolation, the decision must be that (1) is most in harmony with the character of the Book of Proverbs; but it is not strange that Pharisaism, in its very name, separating and self-exalting, should have adopted (2).