“Though we cannot think alike, may we not love alike? May we not be of one heart, though we are not of one opinion? Without all doubt, we may. Herein all the children of God may unite, notwithstanding these smaller differences.”

To Die Before Death: The Sufi Way of Life (1997)

Homesick In Heamoney

As quoted in Simply Living: The Spirit of the Indigenous People (1999) edited by Shirley A. Jones

Fifth Mansion, Ch. 3, translated by the Benedictines of Stanbrook (1921), revised and edited by Fr. Benedict Zimmerman (1930); reprinted (2003) by Kessinger Publications, p. 109
Interior Castle (1577)
Context: We cannot know whether we love God, although there may be strong reason for thinking so; but there can be no doubt about whether we love our neighbor or not. Be sure that, in proportion as you advance in fraternal charity, you are increasing your love of God, for His Majesty bears so tender an affection for us that I cannot doubt He will repay our love for others by augmenting, and in a thousand different ways, that which we bear for Him.

This attribution seems to have begun in the 1960s, and has been debunked at "Who really said that?" by Peter Hughes at UU World (15 August 2012) http://www.uuworld.org/ideas/articles/229844.shtml; previously misattributed in A Chosen Faith (1991) by John A. Buehrens; also in Unitarian Universalist Origins: Our Historic Faith by Mark W. Harris https://web.archive.org/web/20060101061859/www.uua.org/info/origins.html
Misattributed

Part i, canto ii.
Lucile (1860)

Statement on the doorstep of 10 Downing Street, after her election as Prime Minister, as quoted at On this day (BBC) http://news.bbc.co.uk/onthisday/hi/dates/stories/may/4/newsid_2503000/2503195.stm. (This is a paraphrasing of a prayer commonly misattributed to St. Francis of Assisi.)
First term as Prime Minister
Source: [Who wrote Prayer of St. Francis? Doubtful it was friar, San Diego Union-Tribune, 27 January 2009, 28 July 2019, https://www.sandiegouniontribune.com/sdut-1n27prayer00320-who-wrote-prayer-st-francis-doubtf-2009jan27-htmlstory.html, Lord, make me an instrument of thy peace. Where there is hatred, let me sow love; Where there is injury, pardon; Where there is doubt, faith; Where there is despair, hope; Where there is darkness, light; Where there is sadness, joy.]
Source: [The real prayer of Francis of Assisi, Howse, Christopher, The Daily Telegraph, 12 April 2013, 28 July 2019, https://www.telegraph.co.uk/news/religion/9991301/The-real-prayer-of-Francis-of-Assisi.html, That was written in 1912, in French, and published in a pious magazine edited by Fr Esther Bouquerel. It was attributed to St Francis in 1927 through its having been printed on the back of a picture of the saint.]
Source: [Who wrote Prayer of St. Francis? Doubtful it was friar, San Diego Union-Tribune, 27 January 2009, 28 July 2019, https://www.sandiegouniontribune.com/sdut-1n27prayer00320-who-wrote-prayer-st-francis-doubtf-2009jan27-htmlstory.html, An article published last week in L'Osservatore Romano, the Vatican newspaper, said the prayer in its current form dates only from 1912, when it appeared in a French Catholic periodical. ... Although news to many, the truth about the prayer had apparently been hiding in plain sight. “No one among the Franciscans ever thought it really was by St. Francis,” said Giovanni Maria Vian, the editor of L'Osservatore Romano.]

Source: Pride and Prejudice

Source: 1980s, Illustrating Economics: Beasts, Ballads and Aphorisms, 1980, p. 148