Search help

Frequently Asked Questions

  • What is the Theological Commons?

    The Theological Commons is a digital library of over 80,000 resources on theology and religion. It consists mainly of public domain books but also includes periodicals, audio recordings, and other formats.

    Please see the Acknowledgments page for information on our partners and sponsors.


  • How does Princeton Seminary select material for inclusion in the Theological Commons?

    Selection of materials for inclusion in the Theological Commons is guided by the Library’s Collection Development Policy. Additionally, due to legal restrictions on copyrighted works, the Theological Commons only includes materials that are out of copyright, or for which special permission has been obtained from the copyright holder. Typically, works published before 1923 are unambiguously out of copyright, and such works constitute the vast majority of content in the Theological Commons.


  • What should I do if I cannot find an item in the Theological Commons?

    If you cannot find an item you are looking for, there may be several reasons for its absence. The item may yet be under copyright or it may fall outside the scope of the Library’s Collection Development Policy. It may also not yet have been digitized or brought into the Theological Commons. Contact us to nominate materials for inclusion.


  • What subjects are represented in the Theological Commons?

    The Theological Commons draws broadly from the fields of religion and theological studies, along with relevant material from ancillary disciplines.

    Distribution of Subjects
    Protestantism 15,912 (18.0%)
    History 7,495 (8.5%)
    Catholic Church 7,376 (8.4%)
    Church History 6,381 (7.2%)
    Language and Literature 4,696 (5.3%)
    Theology 4,553 (5.2%)
    Philosophy 3,760 (4.3%)
    Music 3,401 (3.9%)
    Practical Theology 3,307 (3.8%)
    Missions 3,267 (3.7%)
    Bibles 3,089 (3.5%)
    New Testament 3,020 (3.4%)
    Religion 2,914 (3.3%)
    Worship 2,821 (3.2%)
    General Works 2,254 (2.6%)
    Old Testament 2,236 (2.5%)
    Ecclesiology 2,016 (2.3%)
    Social Sciences 1,324 (1.5%)
    Preaching 1,243 (1.4%)
    Education 935 (1.1%)
    Psychology 932 (1.1%)
    Fine Arts 923 (1.0%)
    Bibliography 795 (0.9%)
    Judaism 715 (0.8%)
    Ethics 591 (0.7%)

  • What institutions have contributed digital resources to the Theological Commons?

    The Theological Commons includes books scanned at libraries and cultural institutions both nationally and internationally. The largest percentage of works in the Theological Commons has been contributed by the Princeton Theological Seminary Library.


  • For some books, the “Search within this book” option and “Copy to Kindle” button are unavailable. Why?

    The digital text file used to search each book, and to create its Kindle version, has been generated by an automated process. The accuracy of each software-generated text file varies due to factors such as the physical condition, typeface, page layout, and language of the original book.

    To ensure a good experience for the reader, we limit the availability of the digital text to books with an estimated error rate of less than 20%, and we make this estimate known in the interest of full disclosure. (Click the “Copy to Kindle” button, when available, to see that book’s estimated error rate.)


  • When I download a PDF file and copy it to my e-book reader, the e-book reader says the document cannot be displayed. Why?

    E-book readers, such as Kindle (excluding Kindle Fire; see below) or Nook, are designed only to display digital text, not digital images of pages from the physical book. The PDF files available in the Theological Commons include the images of the original book. Some e-book readers cannot display such PDF files.

    By contrast, devices such as iPad and Kindle Fire are full-fledged tablet computers, not strictly e-book readers, and therefore those devices can display the PDF files from the Theological Commons.


  • How do I cite materials found in the Theological Commons?

    Please use the following format for citation of materials found in the Theological Commons. Example:

    Schaff, Philip. Christ in Song: Hymns of Immanuel. New York: Anson D.F. Randolph, 1868. Digital Presentation in the Theological Commons, http://commons.ptsem.edu