Were they ‘the marginalised’, ‘the outcast’, ‘the oppressed’ and so on? Were they people perceived to be breaking the Law or an interpretation of the Law?
In Jewish literature from Hebrew Bible texts and through rabbinic literature the range of meanings appear to be relatively stable in Hebrew, Aramaic, and Greek. We might say similar things about Christian Syriac translations of the Bible. One view of the Gospel ‘sinners’ which should be discounted, however, is one which should have long gone away: ‘the sinners’ as ‘the marginalised’, ‘the outcast’, ‘the oppressed’ etc. with whom Jesus was prepared to mingle. There is a lot of discussion about the socio-economic status of ‘sinners’ in Jewish literature (Psalms, DSS, 1 Enoch, lots of rabbinic literature etc.) and the answer is always clear: ‘sinners’ are perceived to be rich and oppressive. In this sense, they can only be ‘marginalised’ in the same way as ‘the 1%’ are marginalised today. What else? The usual uses of ‘sinners’ have interrelated uses. They can be perceived to be beyond the Law (or a group’s interpretation of the Law), beyond the covenant, and act as if there is no God. ‘Sinners’ can therefore be synonymous with ‘Gentiles’, a usage known also from Paul (Gal. 2.15).
What might this mean for the Gospel tradition? It is possible to read all the main uses into the various Gospel passages, though there is sometimes not enough contextual signs to be precise on a number of occasions. Might Jesus’ association with sinners have provoked a reaction for legal issues? Possibly. Passages like Mark 2.15-17 and parables of repentance-return in Luke 15 (esp. the Prodigal Son) might point in this direction. The close association of tax collectors and sinners would point to at least some understandings of ‘sinners’ in terms of wealth and oppression.
But why the controversy in the Gospel? Perhaps, as Dunn suggested, there may be a reflection of some sort of ‘sectarian’ dispute over interpretation of the Law. The suggestion made by others (esp. influenced by Sanders) that the controversies were over Jesus allowing a bypassing of the Temple for forgiveness is problematic not only because of a lack of evidence but because Jesus is criticised for associating with 'sinners': ‘Why does he eat with tax collectors and sinners?’ Or, in the words of Sirach, ‘Who pities a snake charmer when he is bitten, or all those who go near wild animals? So no one pities a person who associates with a sinner and becomes involved in other’s sins’ (Sir. 12.13-14).
Largely based on Ezek. 33, some did look for the repentance-return of sinners, although most texts we have are highly sceptical that this would happen and imply something along the lines of Sirach 12. The Gospel tradition appears to be part of a more optimistic approach. But maybe Sirach and others were right to be sceptical. We don’t find much in the way of success stories in the Gospel tradition (which we might expect if there were plenty of available stories) and it is notable that one we do find—the story of Zacchaeus—is only attested in Luke (who especially liked themes relating to ‘sinners’) and which may have been written up in light of the lack of success. Perhaps this hope for the repentance-return of ‘sinners’ failed to materialise and the reactions were more predictably like that of the rich man of Mark 10.22. And even Zacchaeus only gives up half his possessions (Luke 19.8)…
There is much more to say on this topic, including how it relates to the ongoing survival of such traditions. All the answers can be found in Jesus and the Chaos of History (2015) which has just been published in North America.