Below is a very simple list (using English terminology) of the Mandaean belief system.

A monotheistic belief system
Adam was the first Mandaean who received the religious instructions directly from God.
Last Prophet or teacher is John the Baptist
Only God may take a life - no Mandaean may ever take a life
The Mandaeans do have an elaborate baptism ritual system.
Marriage and children are held in great esteem
There are strict dietary requirements
The Mandaeans have no symbols, no idols, and no images that can be used to pray to
Sunday (with the exception of specific religious holidays) is their holy day
Please refer to Mandaean values pages to get a learn about their moral belief system
Their language is called Mandaic and Modern Mandaic is still spoken in Iran among the laypeople. Also all the priests still speak Mandaic.