He's on Fresh Air a lot and you can still hear his interviews from their podcast archives.
Terry Gross once asked "How do you get up every day and smile at these kids who do drugs, sell drugs, murder, steal?"
Father G replied, "I would rather stand in awe of the burdens these kids bear than stand in judgment of the way they bear them."
To me, as a disgruntled Presbyterian, that sentence sums up what Christianity should be.
And, since you didn't ask, my other favorite quotes of his are:
"Communion is for hungry people; that's all. Jesus said 'Feed my sheep', and he meant it."
"If you aren't offering these kids concrete help, Jesus doesn't care about your prayer meeting."
"Part of doing this is accepting the fact that kids you love will kill kids you love. It's heartbreaking. It's the fallen world."
"I'm still amazed that people are interested in causes of crime *now*. Now, 20 years after the height of the violence. If you weren't in the streets in 1992 and 1993, you probably don't have anything to add to this discussion."
"Gang negotiations? It's silly. Negotiations won't do anything because there's almost no conflict in gang violence. There's violence, tons of it, but there's no conflict. Bangers don't step out hoping to kill, they step out hoping to die."