Wilford Woodruff says he issued the manifesto after revelation for the temporal salvation of the Church.
Wilford Woodruff, Journal, September 25, 1890, 328, The Wilford Woodruff Papers, accessed June 6, 2023
I have arived at a point in the History of my life as the President of the Church of Jesus Christ of Latter Day Saints whare I am under the necessity of acting for the Temporal Salvation of the Church. The United State Government has taken a stand & passed Laws to destroy the Latter day Saints upon the subject of poligamy or Patriarchal order of Maraiage. And after Praying to the Lord & feeling inspired by his spirit I have issued the following Proclamation which is sustaind by My Councillors and the 12 Apostles