land of milk and honey的意思是“a country where living conditions are good and people have the opportunity to make a lot of money”，即“鱼米之乡，丰裕之地，富饶的乐土”。
milk的意思是“牛奶”，honey的意思是“蜂蜜”，为什么这句话会翻译为“鱼米之乡，富饶的乐土”的含义呢？
这句习语源于《出埃及记》，在第三章有这样一段话：
I have surely seen the affliction of my people who are in Egypt and have heard their cry because of their taskmasters.
I know their sufferings, and I have come down to deliver them out of the hand of the Egyptians and to bring them up out of that land to a good and broad land, a land flowing withmilk and honey, to the place of the Canaanites, the Hittites, the Amorites, the Perizzites, the Hivites, and the Jebusites.
上面这段话，讲的是在上帝的指示下，摩西带领他的人民，也就是很多被迫做奴隶的人，摆脱束缚，走向自由。摩西向这些人许诺自己的土地。 而他拥有的土地是流溢着牛奶与蜂蜜的土地。
《圣经》中有个词名为“应许之地”，这个词出自《旧约·创世纪》，以色列的先祖和上帝做了约定，上帝应许其后代将拥有流溢着牛奶与蜂蜜的土地。所以milk and honey并不单单是“牛奶和蜂蜜”，其可以用于指代这样的应许之地。
因此，后来人们就把land of milk and honey表示“富饶的乐土”这样的含义。
例句：
This country is now the fanciedland of milk and honey.
这个国家现在成了人们向往的丰裕之地。
Many Mexicans regard the United States as a land of milk and honey.
许多墨西哥人把美国看成是富饶的乐土。