Anabaptist Mennonite Biblical Seminary supports open access to promote the distribution of scholarship for the benefit of the church. AMBS faculty collaborate with other organizations on joint projects. The AMBS Library staff coordinate campus efforts to make texts freely available on the internet.
According to The Budapest Open Access Initiative, open access to scientific and scholarly literature means "its free availability on the public internet, permitting any users to read, download, copy, distribute, print, search, or link to the full texts of these articles, crawl them for indexing, pass them as data to software, or use them for any other lawful purpose, without financial, legal, or technical barriers other than those inseparable from gaining access to the internet itself. The only constraint on reproduction and distribution, and the only role for copyright in this domain, should be to give authors control over the integrity of their work and the right to be properly acknowledged and cited".
Joshua V. Leto of Duke University Libraries has created a guide to open access resources in religious and theological studies.
Sally Jo Shelton from Oral Roberts University Libraries has created a custom Google search and guide for open access theological journals.
The Internet Archive has digitized a lot of important theological resources. You can search there for theological books. Some are freely available for download and others are available for a limited loan period (similar to a reserve shelf).