You really cannot grow in your knowledge of God if you are full of bitterness or other self-centered sins. There is a moral element in knowing God. Of course, a person might memorize Scripture or teach Sunday School somewhere or earn a degree in theology from the local seminary or divinity faculty, but that is not necessarily the same thing as growing in the knowledge of God and gaining insight into his ways. Such growth requires repentance; it demands a lessening of our characteristic self-focus. To put it positively, it demands an increase in our love, our love for God and our love for others.- D.A. Carson, Basics for Believers: An Exposition of Philippians
Just as knowledge of God and his Word serves as an incentive to Christian love, so love is necessary for a deepening knowledge of God, because it is exceedingly difficult to advance in the Christian way on only one front. Christians cannot say, “I will improve my prayer life but not my morality,” “I will increase in my knowledge of God but not in my obedience,” or “I will grow in love for others but not in purity or in my knowledge of God.” They cannot do it. The Christian life embraces every facet of our existence. All of our living and doing and thinking and speaking is to be discharged in joyful submission to God and to his Son, our Savior.
(HT: Aaron Armstrong)