Matthew 13:10–17

10 And the disciples came and said to Him, “Why do You speak to them in parables?” 11 He answered and said to them, “Because it has been given to you to know the mysteries of the kingdom of heaven, but to them it has not been given. 12 For whoever has, to him more will be given, and he will have abundance; but whoever does not have, even what he has will be taken away from him. 13 Therefore I speak to them in parables, because seeing they do not see, and hearing they do not hear, nor do they understand.14 And in them the prophecy of Isaiah is fulfilled, which says: ‘Hearing you will hear and shall not understand, And seeing you will see and not perceive; 15 For the hearts of this people have grown dull. Their ears are hard of hearing, And their eyes they have closed, Lest they should see with their eyes and hear with their ears, Lest they should understand with their hearts and turn, So that I should heal them.’ 16 But blessed are your eyes for they see, and your ears for they hear; 17 for assuredly, I say to you that many prophets and righteous men desired to see what you see, and did not see it, and to hear what you hear, and did not hear it.

Spiritual blindness greatly hinders people form entering into the Kingdom of God.

Matthew 23:13 “But woe to you, scribes and Pharisees, hypocrites! For you shut up the kingdom of heaven against men; for you neither go in yourselves, nor do you allow those who are entering to go in.

Mark 8:15–19

15 Then He charged them, saying, “Take heed, beware of the leaven of the Pharisees and the leaven of Herod.” 16 And they reasoned among themselves, saying, “It is because we have no bread.” 17 But Jesus, being aware of it, said to them, “Why do you reason because you have no bread? Do you not yet perceive nor understand? Is your heart still hardened? 18 Having eyes, do you not see? And having ears, do you not hear? And do you not remember? 19 When I broke the five loaves for the five thousand, how many baskets full of fragments did you take up?” They said to Him, “Twelve.”

We need to have eyes that can see Spiritual things

Ephesians 1:17–19

17 that the God of our Lord Jesus Christ, the Father of glory, may give to you the spirit of wisdom and revelation in the knowledge of Him, 18 the eyes of your understanding being enlightened; that you may know what is the hope of His calling, what are the riches of the glory of His inheritance in the saints, 19 and what is the exceeding greatness of His power toward us who believe, according to the working of His mighty power.

2 Kings 6:17 Then Elisha prayed and said, “O Lord, please open his eyes that he may see.” So the Lord opened the eyes of the young man, and he saw, and behold, the mountain was full of horses and chariots of fire all around Elisha.

4 Kinds of Spiritual Vision

Insight:
1 Chronicles 12:32  of the sons of Issachar who had understanding of the times, to know what Israel ought to do, their chiefs were two hundred; and all their brethren were at their command;  

Foresight:
Proverbs 2:11 Discretion (Foresight) will preserve you; Understanding will keep you.
Psalm 37:23 The steps of a good man are ordered by the LORD, And He delights in his way.

Hindsight:
Romans 15:4 For whatever things were written before were written for our learning, that we through the patience and comfort of the Scriptures might have hope.

Oversight:
Numbers 3:32 And Eleazar the son of Aaron the priest was to be chief over the leaders of the Levites, with oversight of those who kept charge of the sanctuary.
1 Peter 5:2 Feed the flock of God which is among you, taking the oversight thereof, not by constraint, but willingly; not for filthy lucre, but of a ready mind;