Mark 6:52
We often think of a hardened heart as one that is opposed to God or the things of God. However, as we see the Apostles struggle with who Jesus is, we see something else. A hardened, or calloused heart may just be oblivious to the things of God. The Apostles had already made up their minds about Who Jesus was, and what they expected from Him. Because of that, they couldn’t see Him for Who He was, and how they should relate to Him.