Marc 7:18
And he saith unto them, Are ye so without understanding also? Do ye not perceive, that whatsoever thing from without entereth into the man, it cannot defile him;
Marc 8:17
And when Jesus knew it, he saith unto them, Why reason ye, because ye have no bread? perceive ye not yet, neither understand? have ye your heart yet hardened?
Marc 8:18
Having eyes, see ye not? and having ears, hear ye not? and do ye not remember?
Marc 9:19
He answereth him, and saith, O faithless generation, how long shall I be with you? how long shall I suffer you? bring him unto me.
Marc 16:14
Afterward he appeared unto the eleven as they sat at meat, and upbraided them with their unbelief and hardness of heart, because they believed not them which had seen him after he was risen.
Hébreux 5:11
Of whom we have many things to say, and hard to be uttered, seeing ye are dull of hearing.
Hébreux 5:12
For when for the time ye ought to be teachers, ye have need that one teach you again which be the first principles of the oracles of God; and are become such as have need of milk, and not of strong meat.