In his new book on mentoring, "Guiding Lights: The People Who Lead Us Toward Our Purpose in Life," author Eric Liu interviewed many of the country's best teachers to discover the qualities of true mentorship. The following excerpt tells of Father Greg, a Los Angeles priest who changes the lives of gang members through unconditional love.

Pico Gardens, Aliso Village. Two of the loveliest names to grace the rollof failed twentieth-century public housing experiments. These projectson the city's eastern edge make up the largest zone of subsidized housingwest of the Mississippi. Within them, ten thousand Latino and blackgangsters, clumped into sixty gangs, live a littered, empty-calorie imitationof life.

For six years, starting in 1986, Father Greg Boyle, SJ, was thepastor at Dolores Mission, in the heart of Pico/Aliso. It wasn't longbefore he saw how much more he needed to do than help the helplessmothers, or pray for their boys, or bury them. He started an alternativeelementary school. Then he created Jobs for a Future, a program to teachthese youth how to find and hold a job. Then he created Homeboy Industries,to help the hardest cases get work by running their own nonprofitbusinesses-first a bakery, then a silk-screening shop, now landscapingand graffiti-removal businesses. After his rotation in the parish ended,Greg returned to the neighborhood to run Homeboy. This would now behis ministry.

The saga of Homeboy Industries is something out of an after-school special. The Jesuithomeboy, the gangland priest: didn't we see that one on cable? Indeed,Greg has gotten a lot of media attention, particularly as he's criticized theLAPD's approach of hammering the gangs. He speaks with the polish ofboth a clergyman and a minor celebrity. Some of the lines he uses are,well, recycled. I'd read them in his clips. The stories of the founding, ofthe rescues and acts of salvation, gleam like stones many times held. Yetwhat made them refreshing still is that they were never meant to be anythingmore. They are like stories from the Bible. They are a daily record,a matter-of-fact accounting of the volume of flotsamed lives flowing past.They are a reminder of constant inadequacy. The day I met him he toldme he had just buried his 114th child. Greg is free of pretense that whathe does is visionary or saintly or world-changing. He is a single human,distributing sandbags against the flood; called to imagine that his labors,in the end, will matter.

With his shaved head and goatee, his unfocused drunken eyes, and hisstump of a right arm (a birth defect), Hugo Jimenez was a picture of menace.The words he had for Father Greg at the elevator were hostile too.He said, "I know you-you're the one who doesn't help anyone from ourneighborhood." It wasn't just cynicism. It was a geopolitical commentthat Greg understood well. Hugo was a member of the Marvelosos, a"Mara Villa" gang at war with the "Sorrenos," gangs of the Mexicanmafia, whom Greg more often worked with. He was a gang veteran, hiscompact body filled with scars and screws and rods from the three timeshe'd been shot (at thirteen, fifteen, and twenty; in the arm, stomach, andfemur). Greg was taken aback by Hugo's hostility but quickly recovered.This was a chance to build a bridge to the Mara Villa. That's why hemade sure to get Hugo's number, why he called Hugo early the nextmorning. Hugo came in at nine. He was twenty-five years old. He hadnever held a job in his life. He was, as he put it, "allergic to work." Gregput him on the payroll that very day, putting him to work in the office-covering the phones, doing small chores and odd jobs.

One month earlier, Hugo's father had died of complications from diabetes.Greg learned that in the course of their initial interview. It shapedhis handling of Hugo, as it shapes his handling of so many ex-homies.The young men who pass through Greg's parish may lack motivation andwork skills and capital. But what they lack prior to all of that is a primalattachment. Their "lethal absence of hope," as he calls it, comes from thefact that so many have never been loved and have never been able to lovein return. "Gangs are bastions of conditional love," he says. "Homeboy isa community of unconditional love."

Hugo was one of the lucky ones; he'd had a father, he loved his father.Greg's work was to sustain that attachment. He told Hugo at every turn,"You are exactly what God had in mind," and waited for Hugo to inhabitthat truth. He didn't tell Hugo or anyone else they could be the firstLatino president if they applied themselves. He told them, "You are exactlyenough." He didn't woof at Hugo with lectures. He said, "Youare everything I would want in a son." If Hugo showed up late, Gregwouldn't yell. He would silently wait, until Hugo hurt inside from the forgiveness.If Greg said, "You're doing a good job, son," it made Hugowant to do a better job. When Hugo decided to get custody of his son,Angel, Greg brought the social worker to see Hugo's closets lined withbaby clothes the next size up, ready to be grown into. Greg paid the threehundred dollars to file papers and accompanied Hugo to court. Hugodidn't understand what the judge was saying until he heard, "Full andsole custody to petitioner," and then the hair on the back of his neckstood on end and he looked at Greg and he wanted to cry.

At first, watching and listening to Greg, I was inclined to put some ofhis actions in a box called "strategic" and others in a box called "sincere."Then, gradually, the boxes became indistinguishable; or, at least, the distinctionbecame irrelevant. Greg tells these lost sons, one after another,that they are in fact exactly enough, that they are everything he wouldwant in a son. And he opens up something primordial in them, somethingthat leads, almost on cue, to huge sobbing and release. The wordshe spoke to Hugo, the salve of unconditional love that he applied, he hasapplied to many others as well, often using the very same language. Heknew too that Hugo's loyalty would help him broaden his reach to newgangs. What I realized after a while was: So what? So what if he wantedto reach more people? That is his job. So what if his love was producedand dispensed in large batches? Each dose felt real, and each one healed.

Hugo proved to be a diligent worker. Over the next two years hestarted taking on more responsibilities, using computers for data entryand record keeping, becoming more vital to the operation. The nextchallenge for him, Greg said, will be to assert his value in the world beyondHomeboy Industries. Every Saturday morning Hugo goes to thecemetery to visit his father. He said to Greg once, "I wish I could showhim what I'm becoming. I wish I could see his face, because all I gave himwhen he was alive was grief." Greg answered, "He is seeing you now."And that was enough for Hugo. It was enough to keep him going that day,to get him out of bed the next morning and the morning after that, tohelp him take care of himself and his boy. It was enough to make Hugoresolve, silently, that he wanted to be for Angel the kind of father Greghad become for him.