In the 1980s, when Sikh immigrants from India began arriving in New Jersey in significant numbers, they lacked a proper house of worship, so they set up a tent on a patch of dirt and began to pray.

Much has changed since then. The tent in Glen Rock, a town in northern New Jersey, has been replaced by an imposing gurudwara, or temple, with a red brick facade and white domes. The congregation that once comprised 10 families now has hundreds of families drawn from across New Jersey and New York, two states that have among the largest populations of Sikhs in the country.

Today, after a long history of dealing with bigotry, Sikhs have begun to acquire power.

The worshipers in Glen Rock include Gurbir Grewal, New Jersey’s attorney general, and Ravi Bhalla, the mayor of Hoboken, along with Mr. Bhalla’s older brother Amardeep Singh, a founder of the Sikh Coalition, a national civil rights organization.

All three grew up together and have attended the temple since they were children — Mr. Grewal and Mr. Bhalla served as best man at each other’s wedding. They are now in their 40s and embody the political maturation of Sikh Americans. They gathered recently in a conference room at the temple to reflect on how their faith has shaped their progressive values.