by Laura Springer, M.Div., Th.M.Biblical theology traces an idea, word, or theme in a biblical book, author, genre, testament, or the entire Bible. While the process can be long and involved and requires careful thought, the steps are quite simple.
- Determine the idea, word, or theme to be studied. In this example, I will use the word "heart" (Gk. kardia) in Matthew's Gospel. You can use the search tool at biblestudytools.com. I used it, chose "interlinear" in the sidebar, and clicked "kardia" to fine all the uses of kardia in Matthew.
 - Next, read each verse in its paragraph (!!!) and determine what this particular verse says about the idea, word, or theme.  Make brief notes.
 - Matthew 5:8 can be pure; related to the perception of God
 - Matthew 5:28 can sin
 - Matthew 6:21 intention revealed in use of treasure
 - Matthew 9:4 related to response; ca do evel/good
 - Matthew 11:29 can be humble
 - Matthew 12:34 source of speech content; evidence of character
 - Matthew 12:40 interior
 - Matthew 13:15 related to understanding
 - Matthew 13:19 can have content stolen by evil one
 - Matthew 15:8 can be communal (had by a community); determines intention
 - Matthew 15:18-19 source of speech content/behavior
 - Matthew 18:35 location of true forgiveness of others
 - Matthew 22:37 able to love
 - Matthew 24:48 source of decisions/behavior
 - Spend time reading over your notes. Look for the structure of the concepts, write the key concepts in bullet form, and cite the appropriate passages.
 - moral component, 5:8; 5:28; 9:4; 11:29
 - cognitive component, 5:8; 13:15
 - volitive component, 6:21; 9:4; 15:8; 15:18-19; 18:35; 22:37; 24:48
 - character component, 12:34-35; 15:18-19
 - vulnerable to evil, 13:19
 - Read through the passages in their groupings and create a full sentence outline of the biblical theology.
 - The heart is the location of our moral decision-making (5:8; 5:28; 9:4; 11:29).
 - The heart is the gatekeeper and ultimate means of understanding (5:8; 13:15).
 - The heart decides our thoughts, motivations, and behaviors (6:21; 9:4; 15:8; 15:18-19; 18:35; 22:37; 24:48).
 - The heart is the reservoir of character (12:34-35; 15:18-19).
 - The heart is vulnerable to evil attack (13:19).
 - You now have a biblical theology of the idea, word, or theme you have studied. 
 - Now, venture out on your own and trace heart in Mark's Gospel.  If you would like, post your results in the comments.