In righteousness; i.e. joined with righteousness equivalent to "righteous." In Proverbs 3:16 the Septuagint has an addition which may perhaps be an echo of this passage: "Out of her mouth proceedeth righteousness, and she beareth upon her tongue law and mercy."
But more probably it is derived partly from Isaiah 45:23, and partly from Proverbs 31:26. There is nothing froward or perverse in them. In the utterance of Wisdom there is nothing crooked, no distortion of the truth; all is straightforward and direct.