David M. Freidenreich, “Food and Table Fellowship,” in The Jewish Annotated New Testament, second edition, edited by Amy-Jill Levine and Marc Zvi Brettler (Oxford: Oxford University Press, 2017), 650:
Although Mark reports that Jesus “declared all foods clean” (7.19), it is clear from context and parallel passages (Mt 15.1-20; Lk 11.37-44) that this phrase constitutes a late and historically inaccurate interpretation of Jesus’ lesson. In these narratives, Jesus does not reject the dietary laws of the Torah but rather dismisses the Pharisaic requirement that food be consumed in a ritually pure fashion. The Hebrew term for “impure,” ṭame’, refers both to ritual defilement of the type that concerned the Pharisees and also to moral defilement caused by sinful behaviors such as those listed in Mk 7.21-22; Jesus teaches that one should worry primarily about the latter.
The Amateur Exegete 