Having neither read the book, nor been particularly familiar with the song, it's hard to know how they and their religious elements compare to those of the film. Reed's son uses the describes how heroin makes him feel "just like Jesus' son" to "convey the power, the feeling of pleasant self-aggrandizement, that overwhelms him when he is high".1 The book apparently has redemption at it's core in such a way as to link it to the influence of "the Savior". Yet the most overtly religious moment in the film is a visual clue, and it's certainly possible that the film alters the original work in some respect.
The shot shown below appears about half way through the film, is the key to unlocking a deeper level of meaning. In combination with the film's title and various minor visual indicators, such as crosses in the background and so on, it invites some kind of religious interpretation.In addition to the religious imagery there is also his encounters with people of faith - in particular the "Mennonite" couple he encounters towards the end of the film. FH finds the wife's singing eerily compelling, and visits the house frequently. When one day he is drawn inside he is discovered by her husband. His response - "Take what you want" - may be one of the classic responses to a household intruder, but the manner in which it is spoken suggests a genuinely free invitation from someone who holds his belongings lightly. Since we know that FH has also, in some sense, "wanted" both his own freedom from his drug problem and this man's wife, it only makes the ambiguity of the statement all the more intriguing.
But Jesus' Son is neither a conventional film about Jesus, nor even one which contains a Christ figure. The lead character, unnamed and credited only as FH, is occasionally helpful to people, but it's nothing particularly noteworthy. All too often his vague good intentions are thwarted because he is incapacitated, and, as he is nearly always high, he often makes things worse for those around him instead. It's only in the third and final act, when he begins to get rehabilitated, that he is able to genuinely help people, Even then it's something he has to learn, rather than something that comes naturally.
Instead the film takes an unconventional approach linking its story to Jesus' death and resurrection. FH's relationship with Michelle is his journey to the cross - before they meet he doesn't appear to be a heavy drugs user, and only once she dies is he mysteriously able to free himself from their power. The transition between the death section of the film and the resurrection / ascension parts of the film is marked by a kind of burial scene. It evokes memories of Christ's death for reasons that are, at this stage, unclear to me, but I suspect it's some kind of visual reference to a piece of Christian Art. This is followed by FH overdosing on a huge pill that's "like an Easter thing".Then there is, of course, the soundtrack which ends on Wilco imploring his listeners to "turn your eyes to the Lord of the skies" (from 'Airline To Heaven'). Various other sings add to the film's meaning, but what is perhaps most surprising, and no doubt significant, is the absence of Reed's'Heroin'. Perhaps this is because the book / film is something of a riposte to Reed's more pessimistic take on the allure of drugs.
It would, no doubt, be possible to revisit the film and speculate as to a host more specific allegories. Is the hand-gliding, naked woman meant to represent an angel etc. etc.? I suspect, however, that this would be to push things too far.
Ultimately, though, the film's major theme - like that of the book, is redemption, but not a redemption that comes from within. The 'crown of thorns' that we see on his forehead through the café window has been superimposed onto him without his knowledge. Whilst it's likely that FH recognises the religious nature of the Mennonite woman's singing, he is drawn to more that just the music. Furthermore, Reed's phrase "Jesus' son" is used here somewhat ironically. The film / book turn Reed's use on it's head - FH is Jesus's son because in the midst of all that is going on someone is looking out for him. Aside from the film's religious elements, this is an impressive piece of filmmaking which seeks to epitomise the life of regular drug users. Avoiding the clichés of living in squalor and the onset of cold turkey, Jesus' Son shows us a life totally absorbed by drugs of any and every kind. When an alcoholic friend of FH offers him the chance to earn some quick money, he finds himself pulling out the copper wiring from his friend's house: it's scrap value will give them enough for another night being drunk and high.
The episodic nature of Jesus' Son is, in part, due to the book which is described as a collection of stories rather than a single novel. But it also conveys the sense of passing in and out of real life, episodes that are vivid and memorable and others that are at best hazy, and at worst forgotten. Indeed, the jumping timeline, and the strangeness and incompleteness of many episodes leaves the viewer feeling a little hazy. But like FH's own journey, we begin to see things with more clarity as we enter the film's final act and see a man that was lost, become found.
1 - Tim Parrish, "Jesus on the Mainline: Lou Reed and Denis Johnson's Jesus' Son." Journal of Religion and Popular Culture - Vol VII. Summer '04