I can see how *Christian books* could be useful; however, there are so many [Christian books][1] out there; *Christian books* may just be too broad.  You might still find yourself having to explain and search for more specific adjectives.

Here are some additional suggestions:   

- **The 27 Books**  
- **Primary Apostolic Writings**    
- **Primary Christian Writings**  

	
Reading through the conversation in the comments to [this answer][2], about Holy/divine writings, I am reminded of an old term, "Holy Writ," and wonder if the word *writ* might be employed:  

- **Apostolic Writ**  
- **Christian Writ**

*Christian Writ* strikes me as an exceptional over-all option, in that it:  

- defines the collection specifically as what the Christians/Apostles wrote,  
- is concise and natural enough to bear up under repetition in lengthy discourse,   
(is even one syllable shorter than "New Testament.")
- respectfully conveys that the Christians consider the collection divine/holy,   
without implying whether one agrees or disagrees with their conviction. 
- *writ* does not seem to be used for other Greek/Christian writings   
(such as the church Fathers, or contemporary books/documents).  


*Christian Scripture* also puts ownership of the conviction on the Christian; however, it may not be distinct enough to represent only the books written by Christians, since the whole of their bible, both parts together, is held by Christians as *Scripture*.  

A bit more eccentric:  
  
-  **The Christian Rule of Faith**  
-  **The Christian Anthology**   

It might be helpful to refer to the collection by its components:  

-  ***Gospels, Acts, Letters and Revelation***,   
either list them, or refer to the particular part that is pertinent to conversation.  

Terminology that might be useful in reference specifically to the original Greek manuscripts:

-  **Greek Canon**,  
-  ***Christian Greek Canon***, 
-  or some of the above suggestions, replacing *writings* with *documents*, *manuscripts*, *parchments*, or *corpus*.

A bit too obscure:  
[*Early Christian writings*][3]   
[*Greek Christian writings*][3]   
[*Apostolic writings*][4]

One might think using *earliest* instead of just *early* would remedy this; however, *earliest* has connotations concerning (carbon) dating of the manuscripts and if you merely intend to imply *foundational*, then, *primary* would be the word of choice, as *foundational* would be a mouthful.

I don't intend to solve the matter with "an answer" but rather to present a compendium of vocabulary, terms, and adjectives adjectives; to consider the various implications, connotations, and limitations; to thus help equip/prepare those who endeavor to communicate respectfully and effectively about such matters in inner faith dialogue.



  [1]: http://www.christianbook.com/
  [2]: http://judaism.stackexchange.com/q/73806/2411
  [3]: http://www.earlychristianwritings.com/
  [4]: http://www.churchhistory101.com/century2-p2.php