ULTON J. SHEEN read every word St. Thomas Aquinas ever wrote, at least once. He often repeated the Latin phrase «TIMEO VIRUM UNIUS LIBRI» (a phrase attributed to the Angelic Doctor) and I encourage you to look it up when you get a chance—it will become obvious why I mention it here.
Most Catholic priests pronounce Latin as follows:
(PDF) Guide No. 1 * * Very Good
Proper of the Mass (Carlo Rossini, 1933)(PDF) Guide No. 2
Parish Book of Chant (CMAA, 2008)(PDF) Guide No. 3
Mass & Vespers (Solesmes, 1957)(PDF) Guide No. 4
Complete Proper of the Mass (Green & Koch, 1946)(PDF) Guide No. 5
the Liber Usualis (Solesmes, 1961)(PDF) Guide No. 6
A Textbook of Gregorian Chant (Dom Gregory Suñol, 1929)(PDF) Guide No. 7
Basic Gregorian Chant (Sister Demetria, 1960)(PDF) Guide No. 8
Chants of the Church (Solesmes, 1953)(PDF) Guide No. 9
Gregorian Chants for Church and School (Goodchild, 1944)(PDF) Guide No. 10
A New School of Gregorian Chant (Johner, 1925)(PDF) Guide No. 11
Fundamentals of Gregorian chant (Heckenlively, 1950)(PDF) Guide No. 12 • 47-Page Book
Correct Latin Pronunciation acc. to Roman Usage (De Angelis, 1937)
Fr. Carlo Rossini’s version is probably the best.
PAY CAREFUL ATTENTION to the “common pitfalls” Americans fall into, like saying “ihn” instead of “een” for the Latin word in. Or saying, “ih-mack-yoo-lah-tuh” instead of “ee-mah-coo-lah-tah” for the Latin word immaculáta. Or saying “Doe-mee-nay” instead of “Doh-mee-neh” for the Latin word Dómine. That being said, these rules can be taken too far. I’ve served the Latin Mass for priests from all over the world: Australia, Austria, Germany, France, England, America, Mexico, China, Puerto Rico, and so on. It is rare to hear a priest say “CHEH-lee” for the Latin word cæli. Most say “chay-lee,” and there’s no use losing sleep over this!
Keywords: “Latin Pronunciation Guide”