"Creator ineffabilis" (Latin for "O Creator Ineffable") is a Christian prayer composed by the 13th-century Doctor of the Church Thomas Aquinas.
It is also called the "Prayer of the St. Thomas Aquinas Before Study" (Latin: Orátio S. Thomæ Aquinátis ante stúdium) because St. Thomas "would often recite this prayer before he began his studies, writing, or preaching.
"[1] Pope Pius XI published this prayer in his 1923 encyclical letter on St. Thomas Aquinas, Studiórum Ducem.
[2] It is now among the most well-known prayers attributed to Saint Thomas Aquinas.
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