"I do not think of political power as an end. Neither do I think of economic power as an end. They are ingredients in the objective which we seek in life. And I think that end or that objective is a truly brotherly society, the creation of the beloved community."

"When I talk about power and the need for power, I’m talking in terms of the need for power to bring about the political and the economic changes necessary to make the good life a reality.  I do not think of political power as an end.  Neither do I think of economic power as an end.  They are ingredients in the objective which we seek in life. And I think that end or that objective is a truly brotherly society, the creation of the beloved community."

     Martin Luther King, Jr., in "The march in Mississippi," a CBS News special report dated 26 June 1966.
     I am posting this for Suzanne Smith, Reference and Instruction Librarian at Multnomah University, who, with the help of Daniel Smith, Research, Instruction, and Digital Services Librarian at Garrett-Evangelical Theological Seminary and a special collections librarian at the University of Mississippi, tracked this to source over the listserv ATLANTIS on 7 August 2019.
     The quote often appears with the following minor errors in transcription (as well as an erroneous reference to “Too Many Cooks, Too Much Spice," The Christian century 83, no. 28 (July 13, 1966):  880-881) as:

I do not think of political power as an end. Neither do I think of economic power as an end. They are ingredients in the objective that we seek in life. And I think that end of that objective is a truly brotherly society, the creation of the beloved community.

Three examples of the errors alluded to immediately above, as supplied by Suzanne:

Garrow, Bearing the Cross, p. 488 [two omissions and one error, correct source is listed at the end of end note 14]: 

When I talk about power and the need for power, I’m talking in terms of the need for power to bring about the political and economic change necessary to make the good life a reality. I do not think of political power as an end. Neither do I think of economic power as an end. They are ingredients in the objective that we seek in life. And I think that end or that objective is a truly brotherly society, the creation of the beloved community. 

King Center [wrong source and two errors, as of early August 2019]: 

In a July 13, 1966 article in Christian Century Magazine, Dr. King affirmed the ultimate goal inherent in the quest for the Beloved Community: 'I do not think of political power as an end. Neither do I think of economic power as an end. They are ingredients in the objective that we seek in life. And I think that end of that objective is a truly brotherly society, the creation of the beloved community' 

Baunoch, ed., Foundation Theology 2006: Faculty Essays for Ministry Professionals, p. 73 [omits “or” between “end” and “that”; also wrongly cites July 13, 1966 Christian Century article as the source in footnote 19]: 

I do not think of political power as an end. Neither do I think of economic power as an end. They are ingredients in the objective that we seek in life. And I think that end, that objective is a truly brotherly society, the creation of the beloved community.