George Tyrrell (February 6, 1861 – July 15, 1909) was a Jesuit priest (until his expulsion) and a Modernist theologian and scholar. His attempts to evolve and adapt Catholic teaching in the context of modern ideas made him a key figure in the Modernist controversy within the Roman Catholic Church in the late 19th century.
Tyrrell was born in Dublin, Ireland and brought up as an Anglican. He converted to Roman Catholicism in 1879. Joining the Jesuits in 1880, Tyrrell was ordained to the priesthood in 1891. He argued, contrary to Church teaching, that the Pope must not be an absolute autocrat in the Church, but rather, a "spokesman for the mind of the Holy Spirit in the Church", the "Base Community" as he termed it, of the laity.
Tyrrell argued that most biblical scholarship and devotional reflection, like the quest for the "historic" Jesus involves elements of self-conscious self-reflection. His famous image, criticizing Adolf von Harnack's human view of Scripture is of peering into a well, in which we see our own face reflected in the dark water deep below:
- "The Christ that Harnack sees, looking back through nineteen centuries of Catholic darkness, is only the reflection of a Liberal Protestant face, seen at the bottom of a deep well." 
Tyrrell was disciplined under Pope Pius X for claiming "the right of each age to adjust the historico-philosophical expression of Christianity to contemporary certainties, and thus to put an end to this utterly needless conflict between faith and science which is a mere theological bogey."
Tyrell was expelled from the Jesuit order in 1906 and suspended from the sacraments the following year. He was given extreme unction on his deathbed in 1909, but was denied burial in a Catholic cemetery. A priest, his friend Henri Bremond, who was present at the burial made a sign of the cross over Tyrrell's grave. For this act Bremond was suspended a divinis by Bishop Peter Amigo of Southwark  for some time.
- Hard Sayings: A Selection of Meditations and Studies
- External Religion: Its Use and Abuse
- Lex orandi: or, Prayer & Creed
- Lex credendi: A Sequel to Lex orandi
- Through Scylla and Charybdis: or, The Old Theology and the New
- Medievalism: A Reply to Cardinal Mercier
- The Church and the Future
- Brief biographical notes on George Tyrrell
- Michael Morton, "Catholic Modernism (1860–1914)"
- International Catholic University: James Hitchcock, "Introduction to Modernism": George Tyrrell, among essays headed "Note: Most of the works dealing with Modernism are sympathetic to the Modernists, and students should maintain a critical stance towards the assigned readings."
- Liberal Catholicism
- Works by George Tyrrell at Project Gutenberg
- Petre, Maude. Autobiography and Life of George Tyrrell. London: E. Arnold, 1912. volume 1 (1861-1884); volume 2 (1884-1909).
- May, J. Lewis. Father Tyrrell and the Modernist Movement. London: Eyre and Spottiswoode, 1932.
- Ratté, John. Three Modernists: Alfred Loisy, George Tyrrell, William L. Sullivan. New York: Sheed & Ward, 1967.
- Schultenover, David G. George Tyrrell: In Search of Catholicism. Shepherdstown, West Virginia: Patmos Press, 1981.
- Sagovsky, Nicholas. On God's Side: A Life of George Tyrrell. Oxford: Clarendon Press, 1990.
- Wells, David F., The prophetic theology of George Tyrrell, 1978.
- Wells, David F., The pope as antichrist : the substance of George Tyrrell's polemic, 1972?cs:George Tyrrell