Jesus told us exactly how it works, so we need not guess:
Matthew 13:10 And the disciples came, and said unto him, Why speakest thou unto them in parables?
Matthew 13:11 He answered and said unto them, Because it is GIVEN UNTO YOU to know the mysteries of the kingdom of heaven, but to them IT IS NOT GIVEN.
Matthew 13:12 For whosoever hath, to him shall be given, and he shall have more abundance: but whosoever hath not, from him shall be taken away even that he hath.
Matthew 13:13 Therefore speak I to them in parables: because they seeing see not; and hearing they hear not, neither do they understand.
Matthew 13:14 And in them is fulfilled the prophecy of Esaias, which saith, By hearing ye shall hear, and shall not understand; and seeing ye shall see, and shall not perceive:
Matthew 13:15 For this people's heart is waxed gross, and their ears are dull of hearing, and their eyes they have closed; lest at any time they should see with their eyes and hear with their ears, and should understand with their heart, and should be converted, and I should heal them.
Matthew 13:16 But blessed are your eyes, for they see: and your ears, for they hear.
Jesus said: "Because it is given unto you to know the mysteries of the kingdom of heaven, but to them it is not given."
You are either GIVEN eyes to see by God, or you are NOT GIVEN eyes to see - there is no 'in-between' (fence). No amount of studying or formal college degrees can give one eyes to see, only God can GIVE that to someone.
Faith does not come by physically hearing, or physically seeing (studying, reading). Faith comes when we are GIVEN ears to hear with spiritual ears, and GIVEN eyes to see with spiritual eyes. That is how the Holy Spirit teaches:
1 Corinthians 2:12 "Now we have received, not the spirit of the world, but the spirit which is of God; that we might know the things that are freely GIVEN TO US of God.
1 Corinthians 2:13 Which things also we speak, not in the words which man's wisdom teacheth, but which the Holy Spirit teacheth; comparing spiritual things with spiritual.
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."
Christ's words "are spirit," and "the Holy Spirit teaches comparing spiritual things with spiritual," and "the natural man receives not the things of the spirit... for they are foolishness to him and he cannot know them because they are spiritually discerned."
John 6:63 "It is the spirit that quickeneth; the flesh profiteth nothing: the words that I speak unto you, THEY ARE SPIRIT, and they are life."