William P. McKenzie (1861-1942) was born in Almonte, Ontario, Canada, and died in Cambridge, Massachusetts. He attended Knox College and Upper Canada College in Toronto, Ontario, before studying theology at Auburn Seminary in Ohio. In 1890 he was ordained a Presbyterian minister. While teaching English at the University of Rochester in 1891, he had a nervous breakdown and was admitted to a sanitarium in Dansville, New York. There he met Daisette D. McKenzie (b. Stocking), while she was visiting, and she introduced him to Christian Science. Through it he experienced healing and began studying Science and Health with Key to the Scriptures by Mary Baker Eddy. He subsequently resigned from both the ministry and from teaching and moved to Toronto, where Daisette was working to establish Christian Science. William and Daisette were married in 1901. William became an executive member of the First Church of Christ, Scientist, in Boston, Massachusetts on October 6, 1894. In 1895 Eddy invited William and Daisette to visit her at her home in Concord, New Hampshire, and in 1896 she summoned William to Boston to serve on the Bible Lesson Committee and to help organize a Christian Science church in Cambridge. Also in 1896 he was made a First Member of The Mother Church and was elected to the Christian Science Board of Home and Foreign Missions. In 1898 William was appointed a trustee of the Christian Science Publishing Society (serving for 19 years), joined the Christian Science Board of Lectureship (serving for 17 years), worked on a committee to assist Eddy with the Church Manual, cofounded the Christian Science Sentinel, and attended Eddy's last Normal class. In 1901 he was elected First Reader of the First Church of Christ, Scientist, Cambridge, and worked for Eddy with Edward A. Kimball on a revision of Science and Health. From 1895 to 1942 he was listed as a practitioner in The Christian Science Journal, and he began teaching Christian Science in 1911. During a span of over forty years, William held various other roles as well. He served as president of The Mother Church in 1899, 1906, and 1909. At Eddy's instruction, he launched The Christian Science Monitor in 1908. He was editor of the Christian Science periodicals from 1917 to 1920. He rejoined the Publishing Society's trustee board in 1922 for another ten-year period of service, and he was a member of the Christian Science Board of Directors from 1932 until his passing. William frequently wrote articles for Christian Science publications. Seven of his poems were set to music and published in the 1932 edition of the Christian Science Hymnal, for which he also wrote the Preface. His other published works include: A Song of Trust, and other thoughts in verse (1887); Voices and Undertones, in song and poem (1889); Songs of the Human (1892); Heartsease Hymns (1901); and The Sower and Other Poems (1903).

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