Diamond Bar Mourns Loss of a Spiritual Leader

He may have been retired from the ministry for 19 years, but on most days Father Donald Potthoff could be found sitting at the St. Denis Catholic Church reception area greeting people.

He was always, “ready with a smile, a joke, a blessing for anyone who requested one,” said Rev. Msgr. James J. Loughnane with St. Denis.

Father Potthoff died April 22 at the age of 90. His passing was felt throughout Diamond Bar, including by the City Council. Councilwoman Carol Herrera and Mayor Pro-Tem Jack Tanaka spoke fondly of the reverend during the May 1 council meeting.

Black bows were tied to the doors of the church last week.

“He was a 41-year resident of Diamond Bar,” Councilwoman Herrera said. “For 22 years, he was pastor of St. Denis church. He was their founder in 1971.”

She requested they adjourn the meeting in memory of Father Potthoff.

“What an honorable, gentle, kind man Fr. Potthoff was,” wrote Joan Threadgold Stevens. “Remember we have him to thank for the building of the church we all now attend … a strong, gentle giant he was.”

Parishoners packed St. Denis for the reverend’s service on May 1.

Father Potthoff was born Dec. 14, 1921, the younger brother to Anthony and Teresa Potthoff. He attended St. John’s Seminary in Camarillo. He was ordained a priest on May 7, 1949.

He was assigned to different parishes throughout Southern California until May 10, 1971, when he arrived to head the new St. Denis congregation made up of about 900 families.

He oversaw the church’s growth and expansion from an original multipurpose room, according to Msgr. Loughnane. The first mass in the church was offered Dec. 8, 1989, with the church being dedicated on April 1, 1990, with Cardinal Roger Mahony – then archbishop – overseeing the dedication.

After retiring in 1993, Father Potthoff lived in the church’s Rectory, where he could be found most days greeting visitors.

“You touched soooo many lives and you were a beautiful person,” wrote Paul LeRoy in honor of father Potthoff. “Thank you for all the guidance and wonderful memories.”