John 6:52 The Jews therefore strove among themselves, saying, How can this man give us his flesh to eat?

John 7:36 What manner of saying is this that he said, Ye shall seek me, and shall not find me: and where I am, thither ye cannot come?

John 8:27 They understood not that he spake to them of the Father.

John 8:43 Why do ye not understand my speech? even because ye cannot hear my word.

1 Corinthians 2:14 But the natural man receiveth not the things of the Spirit of God: for they are foolishness unto him: neither can he know them, because they are spiritually discerned.

2 Corinthians 4:3 But if our gospel be hid, it is hid to them that are lost:

2 Corinthians 4:4 In whom the god of this world hath blinded the minds of them which believe not, lest the light of the glorious gospel of Christ, who is the image of God, should shine unto them.

Ephesians 4:18 Having the understanding darkened, being alienated from the life of God through the ignorance that is in them, because of the blindness of their heart:

Isaiah 29:11 And the vision of all is become unto you as the words of a book that is sealed, which men deliver to one that is learned, saying, Read this, I pray thee: and he saith, I cannot; for it is sealed:

Isaiah 29:12 And the book is delivered to him that is not learned, saying, Read this, I pray thee: and he saith, I am not learned.

Matthew 13:51 Jesus saith unto them, Have ye understood all these things? They say unto him, Yea, Lord.