Adam Clarke on Job 24:2

Some remove the landmarks - Stones or posts were originally set up to ascertain the bounds of particular estates: and this was necessary in open countries, before hedges and fences were formed. Wicked and covetous men often removed the landmarks or termini, and set them in on their neighbors' ground, that, by contracting their boundaries, they might enlarge their own. The law of Moses denounces curses on those who remove their neighbors' landmarks. See Deu 19:14; Deu 27:17, and the note on the former place, where the subject is considered at large.

They violently take away flocks, and feed thereof - Mr. Good translates ירעו yiru, they destroy, deriving the word, not from רעה raah, to feed, but from רע ra, to rend, to destroy. The Septuagint had read רעה roch, a shepherd; and therefore have translated ποιμνιον συν ποιμενι ἁρπασαντες, "violently carrying off both the flock and the shepherd."