The saints are models and examples for us. The world calls them saints but they grieve over their sins. They stand closer to the divineness and that brightness makes them realize even very small failure a sin. For one to have awareness of sinfulness, it needs light of God.
The Ten Commandments is the norm we have to understand sins. This is not a Commandment to restrict us. But it is a Law of Love from a loving father to safeguard His children from being lost.
God has created holy that is the image and likeness of God. In a person besides holiness anything is an addition. So sin is an addition in a person but not holiness.
In spite of our effort to be holy, we fail to do some good thing we desire that is sin. So we are not committing sin but we fail to do Holy Things.
Lent is a time regain the lost percentage of holiness that was established by God at the time of creation. Holiness is the real status of man.