There was a time just after the Watergate scandal when Billy Graham, stung by his ties to the fallen President Richard Nixon, tried to let his hair down a bit.

Graham began addressing a wide range of social issues, including nuclear arms control. He focused less attention on America and said that the church's future was in the Third World. Some long-time supporters began to grumble - literally - about his hair.

"People were worried that Billy was letting his hair get too long. We were getting telephone calls about it," said one insider at the Billy Graham Evangelistic Association, years later.

Eventually, Graham's wife heard about the minicrisis and responded in her own way. Ruth Bell Graham quietly suggested that Billy should consider growing a mustache.

"That was," the insider said, "her way of saying, 'Leave my husband's hair alone. For that matter, leave my husband alone.'" Anyone who has studied the career of the world's most famous evangelist knows that Ruth Graham was much more than his wife or even his "soul mate," the label many commentators adopted after her death on June 14, at the age of 87.

Historians will always ask how Graham evolved from a narrow Southern fundamentalist into the evangelical who preached to the world. Here's one obvious answer: "He married Ruth Bell." She was nothing less than the X-factor, the source of that sense of otherness that, when blended with her husband's essential humanity and North Carolina sense of grace, added a note of mystery to his career. His instinct was to try to get along with everyone. Her instinct was to resist the people who wanted to own him, body and soul.

Graham kept saying, in that "ah, shucks" way of his, that Ruth was smarter than he was. Still, it was hard to determine her precise role.

The basic facts were amazing enough. She was the daughter of missionaries in China and as a girl yearned to be a martyr. She never planned to marry, yet raised five children in their unique North Carolina home (she hired mountain men to combine several abandoned log cabins) that she defended like a lioness.

On one memorable occasion, she kicked her husband under the table when President Lyndon Johnson tried to lure him into political talk. When asked if she had ever considered divorce, Ruth passed along this wisecrack to Barbara Bush: "Divorce? No. Murder? Yes."

It is no surprise that Ruth declined a thousand interview requests for every one she granted. When I left full-time reporting to start teaching, I included this item in my farewell Rocky Mountain News column: "Allowed to interview one living religious figure, I would choose Ruth Bell Graham, the media-shy Presbyterian poet who also happens to be married to the world's best-known Southern Baptist preacher."

I hoped to interview her in 1987, when I spent a day with Graham before a Denver crusade. But the timing was ironic. He was at home, while his wife was away - visiting a clinic due to her already fragile health. Graham offered a tour but admitted that he was not the best guide.

"My wife runs all of this, to tell you the truth," said Graham, mystified by a leather-bound copy of "History of the Reformation in Scotland" on a den table. Ruth, he stressed, was the theologian in the family, the one who could dig into Greek texts.

"She's way over my head when it comes to the books. ... She knows everything about everything in this house. She's collected and read a lot of wonderful things and they're all here somewhere," said Graham, before settling into one of their twin rocking chairs on the back porch, facing the mountains.

"I just wish she were here."

There were, of course, far more days when Ruth missed her globetrotting husband. She poured her emotions into poetry, offering glimpses into a private life behind the very public ministry. Here is one of her poems.

"When / in the morning / I make our bed, / pulling his sheets / and covers tight, / I know the tears / I shouldn't shed / will fall unbidden / as the rain: / and I would kneel, / praying again / words I mean / but cannot feel, / "Lord, / not my will / but Thine / be done." / The doubts dissolving / one by one. / For I realize, / as I pray, / that's why it happened / and this way."

Terry Mattingly is director of the Washington Journalism Center at the Council for Christian Colleges and Universities and leads the GetReligion.org project to study religion and the news.