One of the longest standing cases for a possible underlying Aramaic source in the Gospel tradition is based on Matt. 23.26//Luke 11.41 and the saying concerning the purification of cups:
First clean the inside of the cup, so that the outside also may become clean. (Matt. 23.26)
So give for alms those things that are within; and see, everything will be clean for you’ (Luke 11.41)
The case, made ‘famous’ by Wellhausen and his inspired suggestion, typically claims that Luke appears to have misread the Aramaic דכו (‘cleanse’, ‘purify’) for זכו (‘give alms’) and Matthew is therefore more likely reflecting a pre-Gospel tradition (Black: ‘quite certainly to be found in the wrong understanding of Aramaic dakko’; Casey: ‘represents a misreading’, ‘misread for the original…’). An almost as ‘famous’ critique (not unreasonably) casts doubt on whether it would have been possible to confuse (whether graphically, orally, aurally…) ד with ז.
Still, the two words remain quite similar, do they not? And I wonder whether this is such a problematic issue if we stop thinking about whether Luke made a ‘mistake’ (an ‘honest mistake’?) or ‘misread’ and instead think in conventional redaction critical terms of a more deliberate change (which is only hinted at by Black, though notably in the context of whether ‘the two verbs were originally identical in orthography’). For a start, there is a case to be made for Luke—or Luke’s imagined audience—not understanding the laws surrounding the purification of cups and so a deliberate change could help solve that particular problem. However, when we look at the passage in its immediate literary context, the possibility of an underlying Aramaic source becomes more of a possibility. In Luke 11.42//Matt.23.23, there is again evidence that Luke ‘misunderstood’ (possibly deliberately and polemically) tithing laws in his claim that Pharisees tithe ‘rue’ and ‘all kinds of herbs’ which is precisely not the case according to the Mishnah (m. Shebiit 9.1, ‘Rue, goosefoot, wild coriander, water parsley, and eruca of the field are exempt from tithes…because produce of their type is not cultivated [i.e. grows wild]’). What’s more, we have another potential Aramaic ‘misreading’ here of שבתא (‘dill’; Matt. 23.23) with שברא (‘rue’), a view made ‘famous’ by Nestle in an equally inspired suggestion from 1904. Whether or not Luke could have mistaken ת for ר is perhaps beside the point (Black: ‘misread [quoting Loew]…mistranslation’; Casey: ‘misread’) a redactor certainly could have deliberately changed an Aramaic source so.
And is it not striking that we have two close Aramaic equivalents behind the Lukan and Matthean passages and would this not at least suggest the possibility of an Aramaic source in this instance?