You prepare a table before me in the presence of my enemies;
You anoint my head with oil;
My cup runs over.
The word picture behind "oil" is "life to consume, like water down a stream".
Oil also symbolises the person of the Holy Spirit.
He longs to come like water down a stream to totally consume your life.
Ephesians 5:18 Don’t be drunk with wine, because that will ruin your life. Instead, be filled with the Holy Spirit,
Let the chaos (wine) of your day to day life be put aside and allow the Holy Spirit to fill (consume) you like water down a stream.