At about the time the Rev. Richard Hamilton delivers his sermon, "Living in a Checkered Flag World," at the North Methodist Church Sunday morning, 33 drivers will prepare to take the green flag at Indianapolis Motor Speedway.

The 500 is a kind of holy rite in this part of the country, and for the first time network television will broadcast the solemn, if noisy, proceedings live (WJLA-TV-7, 11 a.m. EDT).

You are likely to hear a great deal about the personalities involved in the 70th running of this race: last year's winner and glamor puss Danny Sullivan; the dynastic families Unser, Andretti and Bettenhausen; A.J. Foyt, who, at 51, is trying for a fifth win at the Brickyard. Above all you'll hear about Rick Mears, the pole-sitter and favorite to win for the third time. His fastest qualifying lap of 217.580 mph is nearly two mph faster than anyone else, which is a very big deal in this game.

But the one most responsible for Mears' prospects, and the man with the highest odds of all to make it to the winner's circle Sunday is a graying invisibility named Roger Penske. Even though Penske is even less of an athlete than the drivers, he is perhaps the most revered man in the sport.

Penske owns the machines that Mears, Sullivan and Al Unser Sr. will drive, and his cars have taken the title here in 1972 (Mark Donohue), 1979 (Mears), 1981 (Bobby Unser), 1984 (Mears) and 1985 (Sullivan). This year, with Mears and Sullivan in the first row and Unser in the second, Penske is sitting pretty once more.

"Nothing is for sure," he said.

"But being in the position to win, being ready to win, that's what we can do before the race begins."

A celebrated racer in the early '60s, Penske now heads the privately owned Penske Corporation, a $700 million business that includes car dealerships, truck leasing firms and industrial-engine distributorships. His Toyota lot in El Monte, Calif., does the biggest volume of any car dealership in the world.

Penske spends about $6 million a year on his racing program. "But Roger just doesn't spend more than everyone else," said Al Unser Sr. "He's developed the best engineers, the best mechanics, the best everything you need in order to win."

Michael Andretti, who is sponsored by Kraco, said, "Penske at Indy is like Ferrari in Formula 1 racing. He's the team to beat."

All week drivers have had to deal with questions such as "can the race be bought?" Always, the answer is "no" but, said Andretti, "Money buys good people, and they make everything happen. You have to live with that in racing."

No one rides the oval in a '60 Fairlane, but there are drivers who are competing with a fraction of the cash and expertise available to Penske's boys.

Phil Krueger, who has worked as a mechanic at Indy for A.J. Watson, qualified as a driver this year in a 1985 model combining parts from wrecks by A.J. Foyt and Herm Johnson. Krueger would have just as good a chance of winning Indy against Penske's cars in a hansom towed by a stoop-shouldered nag.

"When you're not working with an unlimited budget, you have to look for ways to improvise," said Krueger. "On paper this car shouldn't even be in the race."

Like a dozen others, Krueger's car is nearly 10 mph slower than Mears' car, and his position in the eighth row is no help, either. "Turbulence," the wind resistance created by cars in front of the pack, is a word uttered with a weird mixture of reverence and dread on Gasoline Alley.

The Indy 500 is the biggest gathering in the game, and also the biggest gathering of amateur observers. And almost all of them ask the annual question: Are drivers athletes? When the dominant factor in racing seems to be a middle-aged businessman, the question seems fair.

Sullivan certainly looks the part of the dashing athlete. He is the Joe Namath of racing, a fine looking man with a perennial clutch of admirers outside his garage. He has appeared on the cover of Playgirl and soon will be in an episode of "Miami Vice." You could mistake him for any manner of swaggering jock. Sullivan runs, swims and works the weights "to keep myself in shape to drive."

On the other hand, Sullivan acknowledged, "There are a lot of guys in racing who seem to lift nothing heavier than a can of Miller." A.J. Foyt is a balding fellow with a barrel gut and twiggy legs. No one is counting him out.

Being a racer, it seems, is a bit like being a designated hitter in baseball. Slim hips, rippling pectorals and a 4.3 time in the 40-yard dash are not essential. Reflexes, stamina, experience and, said Michael Andretti, "a sense of testing the edge without going over it" are the most important elements in a race driver.

In baseball, teams look for good pitching and big innings; in basketball tough defense and shooting streaks. Racing calls for a similar blend of the preventative and the aggressive.

"What you try to do is finish," said Mears. "If you manage to get to those final laps, then you can worry about winning." Mears, Unser and Sullivan -- Roger Penske's boys -- will be the drivers most likely to make it that far.