Little disclaimer: Most of these thoughts come from a video by Frances Chan.
God and His Son give a clear example of how disciples of Christ are to live.
Jesus says, "If any of you wants to be my follower, you must turn from your selfish ways, take up your cross, and follow me." -Matthew 8:34
When you were a kid, and you played follow the leader, you DID what the leader did. If the leader flapped his arms, you flapped your arms. You certainly did not say, "I will just sit here and flap my arms in my heart. Really, I promise, I'm flapping my arms on the inside."
Imagine if your father asked you to clean your room. How impressed would he be if you came back to say, "Dad, I memorized what you said. I thought about cleaning my room, and I memorized exactly what you told me. Later today, me and some friends are going to have a study about what cleaning my room might look like."
Of course he would NOT be impressed!
We do the same thing with Jesus. He tells us to walk as He walks, and we simply sit and memorize, or we study, or we think. Jesus did not command us to think about what He said, He calls us to DO IT!