A second concern for Lewis was that, without these clear lines, one is tempted to confuse personal preferences with the Christian faith.
“Drawing lines has one very good effect upon the apologist himself. It forces him, again and again, to face up to those elements in original Christianity, which he personally finds obscure or repulsive.” — C.S. Lewis
He viewed this positively because — like the scientist who is tethered to data — the lines of the faith force the Christian to face the facts and to wrestle with them, rather than retreating to his or her preferences, preconceptions or prejudices. This tension between “what the Christian faith is” and “what we want the Christian faith to be” is the stimulus for learning and growth.
The Apostles’ Creed serves as a tether. Whatever we might want the Christian faith to be, whatever we might prefer, whatever we might think in our own thoughts, the Apostles’ Creed tells us what is Christian. This is what Christians have been confessing for 2,000 years.
To use Lewis’ analogy, if we Christians — like the scientist — resist the temptation to simply discard the data that does not fit our preferences and prejudices and continue to wrestle with it, we may discover new heights and depths of understanding.