This passage occurs in the Revised Common Lectionary, Year B
Summary: This is a grand set of verses for Lutherans. It shows a bunch of unclean people eating bread and learning from Jesus; it rebukes the piously proud; and intensifies the law so greatly that we all must confess our sins. As easy and good sermon is clear. I wonder if the challenge is helping people understand how to distinguish between the commandments of God (which Jesus does not abgrotate) and the dictates of men. To put it another way, I think we will all preach a good sermon on law, Christ and forgiveness. But what about that thorny issue -- in the religious soup we call consumer Christian America, what is from God and what is from humanity? And how can we tell?
κοινος ("common" or "defiled", 7:2, 5 and 15 and 20 as a verb) This word can have a range of meanings. "Koine" Greek, for example, refers to the Greek everyone held in common. "Koinonia" means Christian fellowship of the highest degree. κοινος in this case means common, as in unsanctified -- common to the point of being unclean and unfit for duty.
It is worth pointing out that Jesus does not abolish the idea of common/holy. He disorients the previous understandings and then reorients it by including a (laundry) list of sins.
συναγονται ("gather", from συναγω, 7:1) I love this verb! It will come into English as "syagogue" The image here from Mark them is a bunch of people, unclean sinners, gathering around Jesus to hear his teaching and eat bread. There is a congregation here of sinners. The pious are rebuked, but all recognize their guilt.
βαπτιζω ("baptize"/"wash", as noun and verb in verse 4). The word baptize has a host of meanings in ancient Greek related to washing. In this case, it means a ceremonial washing to cleanse something for a holy purpose. What is worth remember here is that the baptism does not simply confer a status but prepares for use. In the same way, our baptisms do not simply confer a status but prepare us for use.
κρατουντες ("hold", from κρατω, 7:3, 4 and 8) This word will come into English in words like "democracy"; it means "hold" but even "sieze" or "rule." We certainly have met people who cling to the law. (See Obama's campaign mistake from 2008.)
παραδοσις ("handed over", 7:3,5,8,9, 13) This word also literally means give over! It can have a generally positive sense of tradition (that which has been handed over); it can also mean betray (again, something handed over). The idea is that tradition is passed over from generation to the next. And lest you think the Bible doesn't like tradition, our whole Communion ritual, Paul declares, is tradition handed over to him.
υποκριτης ("hypocrite", 7:6) The root of this word is theatre, that one answers from stage. Jesus doesn't want us to be actors of the word, but doers.
Translation: meaning of Greek uncertain
The phrase: εαν μη πυγμη νιψωνται
means little to the Greek translator. It literally means "except by washing with the boxing fist." We have no idea what ritual is described here, other than some form of washing. Even with big fat lexicons, sometimes you just don't know what the author of 2,000 years ago meant! Fortunately in this case, the meaning of the passage is not altered.