One thing taught throughout the Bible, and particularly in the New Testament, is that the Christian life is a progression, a journey of the redeemed soul toward God.
Another is that Satan stands to resist every step and to hinder the journey in every way possible. To advance against his shrewd and powerful opposition requires faith and steadfast courage. The epistles call it “confidence.”
In his Philippian epistle, Paul declares his own determination to advance against all obstacles. He says in effect that while he is not yet perfect and has not yet attained unto the goal set before him, he is putting the past behind him psychologically as well as chronologically that he may go on to find in Christ his all in all. “I press on toward the goal,” he says, “to win the prize for which God has called me heavenward in Christ Jesus” (Philippians 3:14). Then with a fine disregard for apparent self-contradiction he urges, “All of us who are mature should take such a view of things” (3:15).
(Borrowed from A. W. Tozer)