"If, in a very public way, that person has acted very strongly against fundamental teachings of church, we can certainly applaud that person in other ways for their particular actions that are consistent with church teaching," Reilly said. "But you can't honor the person as a whole."
Notre Dame students want to make sure that the attention is focused where it should be on Sunday -- on the graduates.
Valedictorian Bollman said that even with all of the media attention and controversy, Notre Dame students are looking at Sunday as a day of celebration.
"That is the most important thing, and listening to what [the] president has to say, his words to send us forth," she said.
The White House is on the same page.
Gibbs said the students will hear from "a president and a commencement speaker that's quite cognizant of the fact that this is a commencement ceremony.
"This is a special occasion for families to celebrate the conferring of degrees in this ceremony and that the president will understand that's the most important aspect of the day," he said.
Obama will be the ninth U.S. president to receive an honorary degree from Notre Dame and the sixth sitting president to address graduates. He will be awarded an honorary doctor of laws degree at the commencement ceremony.
He also will deliver the commencement address at the U.S. Naval Academy May 22.
ABC News' John Hendren contributed to this report.