At Luke 5:8, Peter says, "Go away from me, Lord, for I am a sinful man." Conservative Theologians like to assert that the miraculous catch and Jesus' holy presence suddenly combined to make Peter aware of his own wretched, sinful condition. I'm not so sure Luke (or Paul) thought the same way as Augustine & Aquinas, but let's skip that debate for the moment... I'm going to try fishing with narrative bait today.
On the contrary assumption - that Luke intended Peter's confession to be taken as reference to some particular failing - we must review Luke's narrative to that point for an answer to the question: what sinful act had Peter committed? Aside from being a bad fisherman, there is only one answer. Peter must have been with the people who "tried to keep [Jesus] from going away" after his mother-in-law's healing. And Peter, in particular, had failed to go with Him (or failed to stop him from going).
It is Mark's Gospel in which Peter approaches Jesus himself, and in which Jesus challenges Peter to come along. We certainly, Luke's readers may not have been expected to know this, but we do not need Mark to infer guilt and shame on Peter's part, here. Luke gives it to us. Again, if Luke 5:8 is meant as a specific confession, it can only refer to the morning conflict in Capernaum. Thus, Luke's narrative implies Peter's participation at 4:42, and makes clear in the following sentences that Jesus departed alone. Peter, we see only five verses later, had remained at Capernaum, by the sea.
In this reading, it is only at 5:8 that we realize how Peter felt about Jesus' decision to separate from them there, but Peter's new exhortation (not 'request') also reveals the cause of his own shame. "Go away from me" is not merely a present and future request, but an extension of what Jesus had already done, separating himself from Peter - just a few sentences back. Yet Peter now urges the polar opposite of his previous desires. "Don't go" has become "Go", which means Peter must have become accustomed to being separated from Jesus. Evidently, Peter has also realized his own preference was/is selfishly (& locally) motivated.
While Luke did not imply in chapter 4 that Peter could have gone on with Jesus, Peter now confesses an unspecified failing of some kind. The only substantial inference to be taken from Luke's narrative is that Peter regrets letting Jesus go, or regrets not going along. Once again striking Mark's version completely from our thoughts, we might even suppose Peter assumes himself sinful since Jesus did not stay longer in Capernaum. But whichever the case, one conclusion arises:
If Peter's confession is specific, it must both imply and refer back to their prior encounter, at 4:42. That gives these two events a causal relationship, and serves as a Lukan assertion of chronologicity of the event sequence, at this point.
The implications of this for comparisons with Mark's narrative (and whether Mk 1:16-20 relates a distinct incident from Lk 5:1-11, as many think it does) are best left for some other time. All I'm suggesting at the moment is that Luke intended the narrative sequence from 4:31 to 5:11 to be taken chronologically. This is a first instance of working out ideas I posted on Thursday. Before closing, however, let me here say just another word about generalized vs. specific sin.
Luke gives us no reason to suppose Jesus' holy presence should have been any greater during the catch of fish than it was during a whole day of healings at Capernaum. Likewise, we have no reason to think Peter would be any differently moved by the miraculous provision of food for his family than Peter was by the miraculous provision of health for his family. Despite these similarities, however, Peter's response to Jesus has completely reversed. As far as I can see, there is no reason for this, unless the interim separation was significant for Peter. Thus, theological generalizations about Peter's sinfulness at 5:8 are not only bald faced assertions, they don't necessarily have any grounds in Luke's actual narrative.
It goes without saying that arguments against my reading of Luke 4-5 will be warmly invited. Those who wish to debate various philosophies of sin in general, however, may have to engage with a more Theologically minded opponent. ;-)