You ‘hear’ by becoming repentant. You cannot hear the truth in Jesus’ teachings if your heart is callous.
In Matthew 13:15 & 16, Jesus said: For this people’s heart has grown callous; they hardly hear with their ears, and they have closed their eyes. Otherwise they might see with their eyes, hear with their ears, understand with their hearts, and turn, and I would heal them.’ 16 But blessed are your eyes because they see, and your ears because they hear.
Jesus is praising the disciples for being repentant and able to hear and accept his message of salvation. He is speaking of spiritual eyes and ears.
In Acts 8:21, Simon the Magician is rebuked by Peter because he only believed in Jesus because of the signs and wonders that he saw. He wanted to buy and sell the Holy Spirit.
Acts:21-23 – 20Peter answered: “May your money perish with you, because you thought you could buy the gift of God with money! 21You have no part or share in this ministry, because your heart is not right before God. 22Repent of this wickedness and pray to the Lord in the hope that he may forgive you for having such a thought in your heart. 23For I see that you are full of bitterness and captive to sin.”
You must believe the Bible through a complete repentance.