The knowledge of Christ and a relationship with Him are two separate things. In Ephesians 4:21 Paul reminds the Ephesians of this, Surely you heard of him and were taught in him in accordance with the truth that is in Jesus. As believers who have a relationship with Christ, and who study His word, we are taught the truth of who Christ is and how we are to be a reflection of Him. We have no excuses when we believe in these truths. If we fail, it is because of a conscious decision to rebel against what we know is true.