Explanation: Home thief: the thief within the family. Within the family the most difficult to guard against thieves Usage: The main predicate; as predicate, object; metaphor within the most difficult to prevent bad Source: Puji Song Interpretation "An Zhixiang Wu Deng Hui Yuan division with Fasi": "Q: 'how to house difficult to prevent a thief?' The master said: 'knowledge Debu is wrong'."