SIOUX FALLS - The head of the Diocese of Sioux Falls says he's saddened by Pope Benedict XVI's announcement to resign.

The pope announced Monday that he will resign Feb. 28. The 85-year-old said his advanced age undermines his ability. Benedict is the first pontiff to resign in nearly 600 years.

Sioux Falls Bishop Paul Swain says Benedict is a teacher at heart who has "taught us to contemplate the higher things and to defend truth."

Swain had been appointed by Benedict.

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