{That he had not first washed before dinner} (hoti ou
pr(9374)on ebaptisth(8820)pro tou aristou). The verb is first aorist
passive indicative of aptiz(935c), to dip or to immerse. Here it is
applied to the hands. It was the Jewish custom to dip the hands
in water before eating and often between courses for ceremonial
purification. In Galilee the Pharisees and scribes had sharply
criticized the disciples for eating with unwashed hands ( Mr
7:1-23  Mt 15:1-20 ) when Jesus had defended their liberty and
had opposed making a necessity of such a custom (tradition) in
opposition to the command of God. Apparently Jesus on this
occasion had himself reclined at the breakfast (not dinner)
without this ceremonial dipping of the hands in water. The Greek
has "first before" (pr(9374)on pro), a tautology not preserved in
the translation.