lutching a gold cross and staring skyward in disbelief, the Rev. Paul Engel had little doubt he'd arrived at one of life's crossroads moments. Standing a block from the World Trade Center just before 10 a.m., he watched in horror as the bodies fell. Police officers were urging people to flee, and Engel faced a wrenching choice: Go to the towers and risk death ministering to others, or continue north toward safety.

Not far from where Engel stood, the Rev. Mychal Judge, the Fire Department chaplain, had rushed into that chaotic hell, and that had cost him his life. Judge's sacrifice has often been cited as an example of the heroism that made September 11 so extraordinary. But overlooked are the more ordinary stories of actions that were merely human, not heroic. And those acts have a price as well.

There was nothing about the morning of September 11 that foretold a great spiritual reckoning. Sixty-three years old with clogged arteries, Engel had gone to the gym at the Marriott Hotel by the trade center towers that morning, just like every morning. Running behind that day, he'd skipped the swim portion of his workout and headed right for the lockers. After his shower, as he stood naked save for a cross that had belonged to his late brother, Butch, he heard a screech of metal hitting metal, then a boom. The building moved. "Butch, get me out of here," Engel said, clutching the pendant.

Engel snatched his swim trunks and ran out of the locker room. Windows had shattered, and glass shards cut his feet. Jet fuel and parts from the plane that struck the northern tower had fallen on the hotel, punching a hole in the roof and setting the pool ablaze. He ran down the stairs and outside, as giant pieces of glass from the tower fell around him. Bleeding, he stumbled to the ground underneath a pedestrian overpass. Two men lifted him across the street toward Battery Park City. He asked what had happened, and they told him a single plane had struck the tower. "Thank God it wasn't terrorism," he said. Just then, he looked up and saw the second plane hit.

Across the street, Jim Zamparelli, a friend, helped Engel into his apartment, washed and bandaged his feet, then led him back outside. There, Engel saw an injured man and administered the sacrament of the sick. A police officer approached. "I am a priest; I need to go over there," Engel said. "If you are a priest," the officer answered, "do what you need to do." Engel paused, unsure. Maria Zamparelli, Jim's wife, grabbed his arm and begged him to flee. "You can't go back. It is too dangerous. You are in no condition," she said. Conflicted, Engel turned away from the towers. A few minutes later, at 9:59, the south tower collapsed, crushing the top 16 floors of the Marriott.

Engel emerged from the dust clouds an angry man. In those first few weeks, he delivered Sunday homilies tinged with fire, telling his Bay Head, N.J., congregation of a "new holocaust of death and destruction." Small things irritated him, and he had trouble sleeping. When he did sleep, he had nightmares about his escape. Engel's sister, Therese DiCosmo–a social worker–began to suspect that he was suffering from post-traumatic stress disorder.

Guilt consumed him. His mind constantly drifted back to the moment of decision, and he wondered incessantly why he had not run to the towers. "I should have been stronger," Engel said. "And I wasn't. I was terrified." Friends and relatives all told him the same thing. There was nothing he could do. Had he gone back, he would have died too. His head knew they were right, but his heart wouldn't let him off the hook.

DiCosmo pushed her brother to enter counseling. He resisted, but she wore him down. Gradually, chats with the therapist and the mere passing of time began to help. "I came to realize my own humanity and vulnerability," Engel says. "And I discovered how I need others." On Ash Wednesday, for the first time, he spoke openly of his therapy with the parish and offered a message of hope, not anger. "As Christians," he preached, "finding within ourselves the power of forgiveness and grateful joy can only happen when we open ourselves and acknowledge the need for each other."

But other 9/11 demons linger still. Engel remains uncomfortable with tall buildings and subways, and he panics when he hears loud, sharp noises or airplanes. The guilt and the sadness still hang over him. Engel has returned to Battery Park City, but whenever he passes ground zero, another depression descends.

His sister believes he should make a fresh start and move. "It is a little obsessive to stay," she says. But Engel is determined not to run again. He will remain, rebuild, and remember. "I feel I am supposed to be here," he says. "I am supposed to stay here, to witness and to help people."