The narrow gate is not, as so often assumed, doctrinal correctness. The narrow gate is obedience- and the confidence in Jesus necessary to it. We can see that it is not doctrinal correctness because many people who cannot even understand the correct doctrines nevertheless place their full faith in him. Moreover, we find many people who seem to be very correct doctrinally but have hearts full of hatred and unforgiveness. The broad gate, by contrast, is simply doing whatever I want to do.
Dallas Willard, The Divine Conspiracy, 275.