Separate the Holy from the common

Ezekiel 42:1-20
The north and south rooms facing the temple courtyard are the priests' rooms, where the priests who approach the Lord will eat the most holy offerings - the grain offerings, the sin offerings and the guile offerings.
Five hundred cubits long and five hundred cubits wide, to separate the holy from the common.
Gallery faced gallery at the three levels.
Five hundred cubits = 228.6meters
Why?
Holy life have to separate from the common. Really far away of 500 cubits from the common in physical space.
How?
We are living in this world that full of sins and evil. How can we live holy in this world?  Keep our heart away from the common and focus on the words of the Lord. Dear Lord, please bless my heart, my mind and my strength to serve you.