The fat of the land Genesis 45:17-18 The phrase originates from the story of Joseph and his family, where they ate the best of the animals down in Egypt. The fat of the land refers to when fat was a luxury and so considered the best pick, the cream of the crop.
The love of money is the root of all evil 1 Timothy 6:10 Money is known to cause all kind of problems. Social divisions, thievery, murder, and all sorts of others. Money itself is not inherently evil, but human desires for material wealth causes most problems in this world because of the desire for power in any form.
The powers that be Romans 13:1-2 The powers simply refers to the government. The term "that be" refers to the unstable and temporal nature of human government. In essence, the powers that be are just the mortal government currently in control of your region, as opposed to the kingdom of heaven.
The root of the matter Job19:28 The root of the matter refers to the real problem or the essential part. It could be the base of an argument or the biggest problem in a construction.