In the 1990s, dissatisfied with the Episcopal Church, Mr. Regnery attended two weekend retreats run by Father McCloskey. They became friends, and in 2006 or 2007, he became a Catholic.

Father McCloskey knows that many men “don’t have any friends but their wife,” Mr. Regnery said. “He’s the kind of person, I guess, that if he weren’t a priest, you’d still want to befriend.”

In “Good News, Bad News,” his 2007 handbook on evangelism, written with Russell Shaw, Father McCloskey described the malady of “friendship deficit syndrome,” which he said was “a much bigger problem for American men than it is for American women.” And while he called it a problem, it is obvious that he sees it as an opportunity.

Men today, he wrote, move often for work, which is bad for friendship. All-male schools and social clubs have gone away, depriving men of separate spheres for bonding. Working women need their husbands at home, helping, instead of out socializing with men, which makes them worse husbands by depriving them of the opportunity to practice friendship.

Finally, he wrote, gay culture has hurt male friendship because, “especially in big cities, two men or a small group of men seen socializing” are likely “to draw stares from others and the unspoken question ‘I wonder if they’re gay.’ ” Thus, “many heterosexual men skip the hassles and the embarrassment by not socializing much with other men.”

As an anthropologist of urban male culture, Father McCloskey may hold eccentric views. As a political prognosticator, only time will tell: He has predicted that “culture of life” states, mainly in the South, might someday secede from the pro-gay, pro-abortion-rights rest of the country. As a campus chaplain at Princeton in the 1990s, he knew how to make enemies: He distributed lists of courses that Catholic students should avoid. Even many Catholic conservatives are wary of Opus Dei, which they see as secretive and bizarre — some of its lay members wear a spiked chain, called a cilice, around one leg — and some are repelled by Father McCloskey’s right-wing politics, about which he blogs regularly.

But as a friend, and as a teacher, he seems unimpeachable. A Princeton alumna, who asked not to be named because she works in Catholic circles where Father McCloskey is controversial, said he had introduced her to Catholic authors she had encountered nowhere else.