Changes in American life often slip up on us, especially in an arena as sensitive as that in which religious and secular laws collide.

Yet such changes make a difference.Young Jews entering the business world today might find it hard to believe what happened to Sidney Kwestel during a job interview soon after he was graduated from New York University Law School in 1961.

As an Orthodox Jew, Kwestel told the interviewer his work would be affected by the demands of his faith. Kwestel would have to leave early on Fridays as sundown approached - marking the beginning of the Sabbath. He could not work Saturdays.

Kwestel would, of course, be glad to work Sundays or other extra hours.

The lawyer doing the interview quickly began tossing a tough-edged series of "what if" questions at the young interviewee.

What if he had a Friday afternoon conference? Kwestel said he would avoid scheduling such meetings.

Well, what if a conference earlier in the day ran long? "I would get up and walk out," Kwestel said. "I would have no choice."

The devout young Jew didn't get the job.

This was a common scene.

But when it comes to protecting religious minorities, a "revolution" has taken place in American law, Kwestel said earlier this summer during a talk with Jewish businessmen. He now is president of the Union of Orthodox Jewish Congregations, which includes more than 1,000 synagogues with 1 million members.

Of course, leaders of major law firms and corporations never find it easy to admit they practice religious intolerance.

The interviewer on the other side of the desk from the young Kwestel would have said his decision had nothing to do with religion. It was a matter of maintaining order in the workplace.

And if these policies locked Orthodox Jews, Seventh Day Adventists and other believers with inconvenient faiths out of top jobs, well, this wasn't the fault of the occupants of corporate executive suites.

"It was a uniform policy . . . But it still was a choice between a job and your religion," Kwestel said. Few fought for change. "You weren't supposed to buck the system."

It also didn't help that the vast majority of liberal or inactive Jews didn't follow the laws that created problems. Nevertheless, through the work of a few Orthodox activists, pieces of the legal puzzle fell into place during the 1960s and 1970s.

Kwestel now teaches at the Touro Law School in Huntington, N.J., and is active in the National Jewish Commission on Law and Public Affairs, which works in support of laws protecting the right of Orthodox Jews to practice their faith. He is a former partner of a prestigious Manhattan law firm.

Today, Orthodox Jews and other minorities are supposed to be - and in most cases are - protected by national laws.

But only the future will determine how and if these laws are interpreted to accommodate the growing numbers of American Moslems, Buddhists and others.

Changing societies create new issues. This continues to be true for Orthodox Jews.

Animal rights groups have questioned kosher slaughtering methods. Organ donation programs and laws changing legal definitions of when death occurs have clashed with Jewish traditions. Orthodox Jewish students still can have problems when once-a-year tests fall on religious holidays.

And some ignore laws, continuing to follow policies that establish a comfortable form of prejudice.

Many ask why Orthodox Jews have to be so stubborn. It's hard to explain faith, to explain living with a different bottom line.

"A fundamental belief in Judaism is that these . . . laws came from God," Kwestel said. "We didn't make these laws up. We must follow them."