Grasping the secret of the cross is not something we do once and for all. Sometimes we grasp it, and we are inside the circle of understanding; and sometimes we don’t grasp it, and we are outside the circle of understanding.
For example, after Peter denies Jesus during the passion, the Gospels tell us that “Peter went outside.” They are referring to much more than simply stepping outside through some courtyard door. Peter was stepping outside the circle of both true discipleship and of a true understanding of life. His denial of Jesus took him “outside.” We too, in our following of Jesus, sometimes step “outside” when we give in to temptation or adversity. But then, if we repent, like Peter, we can step back “inside.”
— from the book The Passion and the Cross
by Ronald Rolheiser, page 31