The most common shelf-marks for Theology are:
BR - for Christianity
BS - for The Bible
BT - for Doctrinal Theology
BV - for Practical Theology
BX - for Christian Denominations
Each book has a shelf-mark, which is a combination of letters and numbers. Break this down into sections to make it easier to find the book you are looking for.
Just ask at one of the Enquiry Desks if you can't find what you are looking for - we are here to help.