Genetics and faith.

The 100-year-old staying power of St. George Greek Orthodox Church, Rock Island, is all about DNA and believing - just as it is for the church as a whole.

That is one of the messages being delivered this weekend by Archbishop Demetrios of the Greek Orthodox Archdiocese of America, who is visiting St. George on the occasion of its 100th anniversary.

"A community, which has been able to live - not just survive, but prosper - for three generations ... you have a presence here," Demetrios said Saturday. "You have a presence with achievement.

"That is not an ordinary phenomenon."

Part of St. George's longevity is attributable to genetic makeup, he said.

"Given a scientific analysis, one reason is the DNA of the people," the archbishop said. "It's not accidental DNA. In terms of Greece, for thousands of years before Christ, culture was being produced."

The relatively small Greek Orthodox following ("not in billions like the Chinese") is driven by nature and its faith, he said.

"When you analyze the community, the church here has been the factor of faith, connecting and holding the fabric of the community together," he said. "DNA plus faith equals survival and success."

Demetrios leads a church of more than 1.5 million Greek Orthodox Christians in the United States and spends considerable time traveling. Anniversary events such as the one at St. George is his opportunity, he said, to connect a whole country's worth of Greek Orthodox churches.

"Each place offers a different perspective," he said. "It's good to see how an Orthodox community lives in a different environment.

"This is an opportunity of connectedness, showing none is an isolated unit. I can share what I saw at a recent church celebration in Indianapolis and, at my next speech, I can talk about Rock Island, Illinois."

But Demetrios is known beyond the decorative walls of the Greek Orthodox Church.

He gave invocations at both the Republican and Democratic national conventions in 2000, 2004 and 2008. He also attended each of the presidential inaugural ceremonies that followed.

On the topic of prayer and politics, the archbishop revealed a highly animated side.

He described the conventions as "glamour with substance" and said he is allotted two minutes for his invocation, which is a strictly followed time schedule.

"There was a woman professor of speech or communications who asked whether she could time me in advance - make sure I stay within my time frame," his story began. "I said, ‘Of course, but you must agree to listen and to pray with me.'"

When his prepared invocation was timed at two minutes and 50 seconds, the professor advised him to do some editing.

"Only the Bible is an absolute text," he said. "Anything else can be changed ... so I cut it."

After making his edits, the professor again asked to time him.

"I said, ‘Sure, as long as you pray with me again,' " Demetrios recalled. "She said, ‘Perfect! One minute and 56 seconds.' And I said, ‘Oh, good! I have four more seconds.'

"She looked terrified."

In the end, he said, the convention appearances are "an enjoyable exchange" and so are anniversary celebrations, such as the one at St. George.

"For us as a church and me personally, it's a very important thing for us to be in touch with the community," he said. "Plus, I get a nice reception at the airport."

The archbishop led Heirarchical Great Vespers at the church Saturday, then participated in the church's centennial banquet Saturday night. He will lead services today at 9 and 10 a.m. at the church at 2930 31st Ave.