What does it mean to be ye perfect?

In Matthew 5:48 Jesus Christ said: "Be ye therefore perfect, even as your Father which is in heaven is perfect."

The Word therefore is a reference to the previous verse where He said: "And if ye salute your brethren only, what do ye more than others? do not even the publicans so?" Publican a tax collectors of that day, a term often used in the same breath with the Word sinner.

To be Perfect is to be without defect or without error in what we say or do.

This is a tall order and an impossibility without the Fathers help.