By early afternoon, the thermometer was pushing 100 and the asphalt surface of the Soldier Field parking lot was blistering to the touch. At one edge of the lot, four large, open-sided tents sat clustered and baking in the bright sunlight. In the largest of the tents, a football field-size affair holding some 3,000 chanting Hindu worshippers, it was even hotter.

Inside the tent, acrid, black smoke that spiraled upward from hundreds of small ritual fires fed by clarified butter and Indian spices settled over the crowd. The smoke obscured the 10 orange-robed Hindu priests seated onstage at the front playing instruments, chanting mantras and instructing participants in the intricacies of the ancient ritual.

Yet, despite the horrendous heat, virtually no one left the tent–save a few mothers with crying children. Instead, they sat cross-legged on mats for the 90 minutes their fires burned. For the devotees, the smoke and heat were a spiritually purifying experience, appropriate for their worship of the Sun Goddess Gayatri, who represents the source of all earthly life.

The location was equally appropriate. Hinduism was formally introduced to America in Chicago by Indian religious leader Swami Vivekananda at the 1893 Parliament of the World's Religions. On July 28-30, it was evident just how much the 5,000-year-old teachings of Hinduism–the world's oldest major religion–have become a part of the changing American religious scene.

"The history of Hinduism in America is still being written," said Diana Eck, a Harvard University professor of comparative religion and Indian studies. "It's much too early to say how it will affect this country and how it will ultimately be effected by this society. But clearly it's here to stay and will continue to grow."

The majority of those at Soldier Field were associated with the Gayatri Pariwar sect popular in the west Indian state of Gujarat. They came from as far away as Montreal and California for the ashwamedh yagna fire ceremony, a ritual once reserved for kings. Gayatri Pariwar, which claims followers in 86 nations, is but one of a host of Hindu groups now established here.

Concern for the children was evident at Soldier Field, where several parents asked Pranav Pandya, Gayatri Pariwar's international director, how they could keep their children connected to their Indian roots. "Our children know nothing of the rituals and are losing our values," one mother admitted. In response, Pandya spoke of plans to build as many as 100 Indian cultural centers around the US. Pandya, a 45-year-old medical doctor, also said Hinduism needs to emphasize its "scientific basis." Hindu mantras and rituals, he said, are proven powerful instruments for uplifting individual consciousness and promoting world peace. Not only will this "liberal Hinduism" appeal to westernized Indians, he said, it will also appeal to non-Indian Westerners.

Included in his description of scientific Hinduism was an end to the guru tradition. Traditional Hinduism holds that studying with gurus–enlightened spiritual masters–is essential to spiritual growth. "The time has come to get rid of hero worship," said Pandya, who is billed as Gayatri Pariwar's spokesperson, not its guru.

Yet, the next day, following completion of the afternoon fire ceremony, Pandya, wearing orange robes as a reminder of the Sun Goddess Gayatri, sat on a couch draped with red material as the faithful filed by to pay homage. First they bowed before a chair on which sat the flower-covered sandals of the sect's deceased gurus–Sri Ram Sharma Acharya and his wife, V. Mata Bhagavati Devi Sharma–who were also Pandya's inlaws. Then they bowed before him and touched his feet.

Putting aside his talk of Hinduism's need to modernize, Pandya played the role expected of him by both sari-clad grandmothers with tattooed hands and forearms and by young men with beepers on their belts. Hinduism's encounter with America may someday reshape the ancient faith, as Pandya suggests. But it's clear that beliefs and practices thousands of years old will not soon disappear from the American Hindu scene.

Gayatri Pariwar plans an even grander yagna at Anwalkheda, India, from November 3-7, 1995. In USA and Canada: Gayatri Pariwar, 8413 West North Terrace, Niles, Illinois, 60714, USA. Phone: 708-692- 6036. In India: Shantikunj, Haridwar, Gayatri Shaktipeeth, Anwalkheda District, Agra, UP.