arc, bends toward justice, Boston, Boston University, Civil Rights Movement, civil war, education, Ethics, intellect, justice, Martin Luther King, moral universe, morality, morals, nuclear energy, nuclear industry, nuclear power, slavery, social ethics, Social Justice, Theodore Parker
“They love the exclusive use of certain forms of truth, and neglect justice”
Theodore Parker (1810-1860) is recognized as having influenced-inspired Martin Luther King.  While Parker did not speak of the dangers of the nuclear age, as King did, because there was not one, he discusses the very lack of morality, which makes the nuclear industry possible. The nuclear industry is slowly killing off the world, and has the potential of killing it all at once. Unfortunately, those involved in the nuclear industry appear to lack both morals and intellect, as they themselves are not immune to nuclear dangers. When Parker speaks of “intellect”, he may be using an archaic form meaning wits, senses. Perhaps he means the “certain forms of truth” and education in the most narrow sense.
From Parker’s (1853) sermon III: “OF JUSTICE AND THE CONSCIENCE“. The Bible quote for sermon III is: “TURN AND DO JUSTICE“.— Tobit xiii. 6. Parker foresees the US Civil War in this sermon. He was writing closer to Napoleon’s time, than we are to M.L. King.
“Of Justice and the Conscience” is one of “TEN SERMONS OF RELIGION, BY THEODORE PARKER, MINISTER OF THE TWENTY-EIGHTH CONGREGATIONAL CHCRCH IN BOSTON. BOSTON: CROSBY, NICHOLS, AND COMPANY.NEW YORK: CHARLES S. FRANCIS AND COMPANY.
1853.” Entire book is here: https://archive.org/details/tensermonsofreli00inpark
(Highlights and underline added. Clean original at link.)
The entire text for this sermon is very long.
Although we cannot reproduce Martin Luther King’s works, due to copyright considerations, we can reproduce Theodore Parker, and others, who inspired Dr. King, and those who were quoted by him. We highlighted in orange parts, which seem to have most visibly influenced King’s speeches. 
 Parker preached widely in the Boston area. [a] Dr. King studied theology at Boston University. Transcendentalists were apparently involved in founding Boston U. [b] The book was dedicated to “Ralph Waldo Emerson”, leader of the Transcendentalist Movement. Emerson was also a mentor to Thoreau. [c]
[a] “Theodore Parker (Lexington, Massachusetts, August 24, 1810 – Florence, Italy, May 10, 1860) was an American Transcendentalist and reforming minister of the Unitarian church. A reformer and abolitionist, his words and quotations which he popularized would later inspire speeches by Abraham Lincoln and Martin Luther King, Jr.” http://en.wikipedia.org/wiki/Theodore_Parker
[b] “‘America’s Intellectual Morning’: or, How the Transcendentalists Founded Boston University,” Resources for American Literary Study. An Annual. Vol. 35. New York: AMS Press, 2012, by Wesley Mott: http://emerson.tamu.edu/content/‘america’s-intellectual-morning’-or-how-transcendentalists-founded-boston-university-0
 When Martin Luther King, Jr. spoke on the steps of the State Capitol in Montgomery, Alabama, after the Selma to Montgomery March, on March 25, 1965, in the final sentence found here, he speaks of a moral arc, which is believed inspired by Parker: http://en.wikipedia.org/wiki/How_Long,_Not_Long
He concluded this speech by reading much of the Battle Hymn of the Republic. Had current copyright laws been in effect, such a lengthy reading might have put him at odds with the heirs of the author, Julia Ward Howe, who had died in 1910. 70 years after her death would have been 1980! She, herself, had drawn much from oral tradition with the song, which she published in 1862. http://en.wikipedia.org/wiki/The_Battle_Hymn_of_the_Republic
For King’s August 28, 1963, March on Washington Speech, http://en.wikipedia.org/wiki/I_Have_a_Dream, he most likely took the term “American Dream” from the 1931 book “The Epic of America,” by James Truslow Adams. http://en.wikipedia.org/wiki/James_Truslow_Adams
However, the idea of a dream is found in the above Theodore Parker sermon.
Anyone familiar with oral traditions and preaching should understand that “borrowing” from other works is part of oral and preaching traditions, as also noted here: http://en.wikipedia.org/wiki/Martin_Luther_King,_Jr._authorship_issues. However, where appropriate, King referenced authors in speeches. But, it is very awkward to speak, or even write smoothly, while giving references. Furthermore, preachers of that generation were apparently encouraged to use the sermons of others and to quote extensively from others, especially poems and hymns, in their sermons. Books, similar to Parker’s, were sold for other preachers to use. There were books with famous quotes, and jokes for preachers to use, as well.
The most strange copyright is that of the King James Bible in the UK, which was, until recently, still Crown Copyright! Did they release it to Open Government License for its 500th anniversary? They do allow “fair use” however.
An excellent book dealing with King’s preaching style is “The Preacher King: Martin Luther King Jr. and the Word that Moved America“, by Richard Lischer.