Strong, Douglas M. Perfectionist Politics: Abolitionism and the Religious Tensions of American Democracy. Syracuse, NY: Syracuse University Press, 1999.

There are several recent book-length studies dealing with Lincoln’s religious views:

Fornieri, Joseph R. Abraham Lincoln's Political Faith. DeKalb,IL: Northern Illinois University Press, 2003.

Guelzo, Allen C. Abraham Lincoln: Redeemer President. Grand Rapids: W.B. Eerdmans, 1999. Guelzo has a very perceptive chapter on the “doctrine of necessity.”

Morel, Lucas E. Lincoln's Sacred Effort: Defining Religion's Role in American Self-Government. Lanham: Lexington Books, 2000.

Temple, Wayne C. Abraham Lincoln: From Skeptic to Prophet. Mahomet, IL: Mayhaven Publishing, 1995.

Thompson, Kenneth W., ed. Essays on Lincoln's Faith and Politics. Lanham, MD: University Press of America, 1983.

Winger, Stewart Lance. Lincoln, Religion, and Romantic Cultural Politics. DeKalb, IL: Northern Illinois University Press, 2002. This book includes an excellent chapter on “Poetry and Religious Orthodoxy in the Second Inaugural.”

Wolf, William J. The Almost Chosen People: A Study of the Religion of Abraham Lincoln. Garden City, NY: Doubleday, 1959.

This book traces the development of Lincoln's ethical and moral views in both religious and non-religious terms:

Miller, William Lee. Lincoln's Virtues: An Ethical Biography. New York: Alfred A. Knopf: Distributed by Random House, 2002.

This essay may also be useful:

Thurow, Glen E. “Abraham Lincoln and American Political Religion” in The Historian's Lincoln: Pseudohistory, Psychohistory, and History. Urbana, IL: University of Illinois Press, 1988.

These surveys of nineteenth-century evangelical Christianity and revivals are worth consulting:

Balmer, Randall Herbert. Blessed Assurance: A History of Evangelicalism in America. Boston: Beacon Press, 2000.

Carwardine, Richard. Evangelicals and Politics in Antebellum America. New Haven: Yale University Press, c1993 (in paperback, 1997).

___________. Transatlantic Revivalism: Popular Evangelicalism in Britain and America, 1790-1865. Westport, CT.: Greenwood Press, 1978.

Here’s an online version of Lincoln’s 1846 handbill denying his religious skepticism:

http://showcase.netins.net/web/creative/lincoln/speeches/handbill.htm

This helpful piece on young Edward Lincoln appears as part of the Abraham Lincoln Research Site, mounted by Roger Norton, a former American history teacher:

http://home.att.net/~rjnorton/Lincoln67.html

For the history of Lincoln’s church in Washington, see:

Edgington, Frank E. A History of the New York Avenue Presbyterian Church: One Hundred Fifty-Seven Years, 1803 To 1961. Washington, DC: New York Avenue Presbyterian Church, 1961.

And the church’s own website:

http://www.nyapc.org/

Here’s a brief sketch of Phineas Densmore Gurley, the pastor of New York Avenue Presbyterian:

http://www.nyapc.org/

The Lincoln Online site provides this text of the “Meditation on the Divine Will”:

http://showcase.netins.net/web/creative/lincoln/speeches/meditat.htm

The text of Lincoln’s 1864 letter to Eliza Gurney appears on the same website:

http://showcase.netins.net/web/creative/lincoln/speeches/gurney.htm

These are only the most recent of the many studies of Lincoln’s Second Inaugural:

White, Ronald C. Lincoln's Greatest Speech: The Second Inaugural. New York: Simon & Schuster, 2002.

Tackach, James. Lincoln's Moral Vision: The Second Inaugural Address. Jackson: University Press of Mississippi, 2002.

For the full text of the Address, see:

http://showcase.netins.net/web/creative/lincoln/speeches/inaug2.htm

You may want to see this brief sketch of Thurlow Weed:

http://www.u-s-history.com/pages/h217.html

as well as the full text of Lincoln’s March 15, 1865 letter to Weed about the Second Inaugural:

http://www.hti.umich.edu/cgi/t/text/text-idx?c=lincoln;cc=lincoln; type=boolean;rgn=div1;q1=thurlow;op2=and;q2=weed;op3=and;q3 =1865;view=text;subview=detail;sort=occur;idno=lincoln8;node= lincoln8%3A764

You may be interested to see a photo of Tad and Willie Lincoln during the White House Years considering the profound effect Willie's death had on Lincoln's religious views.

http://www.gilderlehrman.org/search/display_results.php?id=GLC05111.02.0065