Index theologicus (IxTheo) encompases the older Zeitschrifteninhaltsdienst Theologie (ZID) current contents service. It indexes articles in theological journals and essays in selected books from 1984 to date. Journals are indexed within 24 hours of the time they are received at the Tübingen university library, so this is by far the most current theological database. Alas, citations do NOT link to full-text online articles.
IxTheo has both an English and a German interface, and the English interface even has English language subject headings. IxTheo covers both English and European language literature, especially German. Here is a comparison with ATLA in one narrow subject area as of 9/2006.
| ATLA | all years | 1984 - | 1984-, English | 1984 -, non-English |
| article or essay | 295 | 135 | 105 | 30 |
| review | 141 | 107 | 34 | 73 |
| IxTheo | all years | 1984 - | 1984-, English | 1984 -, non-English |
| article or essay | 91 | 91 | 52 | 39 |
| review | na | na | na | na |
You can search for keywords or browse sorted fields. The index button activates browsing. There is also an expert search which has a link to a Scripture References link.
Searching supports logical operators (AND, OR, NOT) and the use of parentheses to group terms. Truncation is automatic. To suppress truncation, use quotes and put a space to terminate the word, like "god " to match god but not gods or godly.
Use the index button to browse a field. You need to understand the "subject heading chain" concept to make sense of the browse display. There is only one subject field in each record, but multiple subjects are entered into the field, each subject separated by slashes. So the subjects make a chain. For example, the image below shows a browse of the word grace. The first line says there is a record with the subject "grace" and the subject "praise of God" and the subject "liturgy" and the subject "confession of guilt". If you browse under praise of God you would also find this record, but the elements of the chain would be rotated so praise of God is the first element. So it is possible to browse any subject in a field/chain.
To search for material on a bible passage, use the subject heading field or use the special expert search scripture reference link at the bottom of the page. There are important differences between these two approaches.
Books of the bible are assigned somewhat unpredictable names such as the following.
Of course this is done to make them uniquely retrievable (e.g. to distinguish a modern person named Matthew from the gospel named Matthew).
To solve the bible name problem, use the "scripture reference" link at the bottom of the screen to open a browseable list of all bible books. In the example below Matthew has been selected. When the search has been executed, you can see it actually searches for "matthew gospel."
Once you have the correct book name, you may continue to use the "scripture reference" and specify chapter and verse using this format:
Alternatively, once you know the correct name for the bible book you can browse it in the subject heading field. Just click the index button. This is far easier than formulating a syntactically perfect search.
If you wish to search subject heading rather than browse subject, use the following format, including the slashes:
timothy letters / I:3:16 /
(timothy letters, space, slash, space, book number, colon, chapter number, colon, verse number)
The University of Tübingen hosts this internet resource at no cost to the public.