Jon Krakauer, after writing the initial story that led to his research for the book, felt that he had a personal connection to Chris, despite never having crossed his path. Krakauer writes that he attempted to be objective, but admits authorial bias in his examination of Chris; to this end, he occasionally uses hyperbole and unnecessary metaphor for dramatic effect. In the case of this quote, he was writing about his perceptions of Chris's final days alive; he bases his feelings entirely on the existing writing and pictures (available below) that survived Chris's death:
...if he pitied himself in those last difficult hours -- because he was so young, because he was alone, because his body had betrayed him and his will had let him down -- it's not apparent from the photograph. He is smiling in the picture, and there is no mistaking the look in his eyes: Chris McCandless was at peace, serene as a monk gone to God.
(Krakauer, Into the Wild, Amazon.com)
This interpretation of Chris's mindset is supported by Chris's various writings and conversations with people about his beliefs. Chris saw his life as a test to be waged against and with nature, to live and risk death in the pursuit of some unknowable epiphany that would set him free from the daily grind of everyday life. Whether he accomplished that epiphany cannot be known, although Krakauer suspects that Chris found what he was looking for at the end. In any case, this is an admittedly subjective interpretation by the author.
this may be too late, but you should know anyway if you dont already.
In this passage, krakauer is refering to the last photo that chris took of himself. he had a camera with him and when his body was discovered, there were a few rolls of undeveloped film inside the bus.
"One of his last acts was to take a photograph of himself, standing near the bus under the high Alaskan sky, one hand holding his final note toward the camera lens, the other raised in a brave, beatific farewell. He is smiling in the photo, and there is no mistaking the look in his eyes: Chris McCandless was at peace, serene as a monk gone to God."
google his name and you should be able to easily find the photo. you can tell by the expression on his face. he knew the end was coming for him, but he seemed to be ok with it. he had accopmlished his mission.
he even says in the note, "i have had a happy life and thank the lord, goodbye and may god bless all".