The truth will make you free," advises a sign on the wall of Sonia Johnson's study, "but first it will make you miserable." Just how miserable, Sonia learned in 1980. Her troubles began last December when she was excommunicated from the Mormon Church for her aggressive support of the Equal Rights Amendment. Church leaders oppose it. A month later her husband of 17 years asked for a divorce. Remembering those days, Sonia says, "I still find myself sobbing."

Now, however, she has been acclaimed a heroine of the women's movement—a cause with little else to cheer about lately. Sonia, 44, became aware of the ERA only two years ago when she returned from overseas where she had been raising four children and following her statistician husband from one job to another. Today she says, "I'm one of the few people in this world who can do anything I choose. I can't tell you how good I'm feeling." Released from marital and religious constraints, she threw herself into the ERA struggle. Mormons for ERA, a group that Sonia helped found and still heads, has grown to 1,200 members. In July her speech on women's rights brought the Democratic Convention to its feet chanting "E-R-A, E-R-A." She even received a $3,000 Hugh M. Hefner First Amendment Award from Playboy for "individual conscience." The check went straight to the National Organization for Women.

Sonia, a fifth-generation Mormon, appealed her excommunication twice this year; both efforts failed. One of her three brothers is so upset he won't talk to her. Nonetheless, Sonia reports, "I still feel Mormon. Those men in Salt Lake City can't decide who's Mormon and who isn't." The lay bishop who excommunicated Johnson, a CIA personnel officer named Jeffery Willis, says he hopes Sonia "will put her life in order" and return to the church.

Sonia believes excommunication did not cause her divorce. "The mid-life crisis," she says ruefully, "hits men harder than women." Her 46-year-old ex-husband, a Mormon convert, has moved to Oregon. Meanwhile Sonia has limited her social life: "I don't have much room in my mind or heart for it."

The divorce gave her the 11-room house in Sterling Park, Va., a Washington suburb, but no alimony or child support. Three of her children, aged 6 to 15, live with her. The fourth, 17, lives in Utah. Sonia commands up to $1,000 per appearance on the lecture circuit (she charges less for pro-ERA functions). A former English instructor with a Ph.D., she is writing a book about her troubles, and Norman Lear may do a movie.

The response to her Democratic Convention speech was so enthusiastic she says, "If I had died then I would have died happy." A month later she led a protest outside Republican headquarters in Washington. "Somehow they had the political acumen not to have us arrested," she complains.

Not so when Sonia and 20 other ERA supporters chained themselves to the gate of a new Mormon temple in Bellevue, Wash, last month. Sonia spent seven hours in jail, paid a $100 fine and boasts, "It was a grand day in my life. Women have to risk civil disobedience for their rights." She is considering a protest at Ronald Reagan's inaugural because of GOP opposition to the ERA.

Johnson may be proudest of what happened at a recent Mormon convention in Salt Lake City when three women opposed a motion affirming the church president as a "prophet of God." "The brethren didn't throw them out or even hint at excommunication," she says. "I guess they didn't want another Sonia Johnson episode."