“A greedy soul stirs up strife.” The Hebrew is more literally a “wide soul” (rahab nephesh) where “wide” is rahab and nephesh refers to a person and/or the person’s appetites. The Hebrew word nephesh (#05315 נֶפֶשׁ), has a wide range of meanings, and the exact meaning is closely tied to the context. As Bruce Waltke points out, “Rahab with concrete nouns denotes breath or width…but in construct with psychosomatic words it denotes unrestraint, immodesty: with nephesh an unrestrained appetite (see Prov. 28:25; cf. Ps. 101:5); with leb [“heart”], of unrestrained thoughts, ambitions, plans, and so on. This heart, recognizes no boundaries to curb its aspirations, behaves as if it were God (Waltke, NICOT, The Book of Proverbs, chapters 15-31, p. 171). Waltke later writes about Proverbs 28:25 and says, “the unrestrained appetite (rehab-nephesh, lit. “wide of appetite”...stirs up strife. ...The greedy person’s insatiable appetite brings them into conflict with others, for he transgresses social boundaries. Not content with his portion, he becomes disruptive and destructive, and those whose person and property he violates fight back. This is how wars are started” (Waltke, p. 427).
“prosperous.” The literal Hebrew is “fat.”