Genesis 1:20-2:4; Psalm 8:4-9; Mark 7:1-13
The Pharisees held that the rules passed down from Moses by oral tradition had equal value to those found written in scripture - and thus we find all sorts of regulations about washing up to the elbows before eating, and so on, being observed in Christ's time.
Jesus was however concerned about our spiritual health, and challenges us to think about what is really important. Mark, writing to a Christian community living in contact with and containing Gentile christians, emphasises Jesus' teaching that those old and challenging rules to live by are actually preventing christians with each background from meeting and sharing meals together!
We should take care that any rules and common practice that we observe are not preventing us from being approachable by those with whom we live.