Why do so many Christian’s misunderstand the Bible?
Hosea 4:6-10 NKJV
My people are destroyed for lack of knowledge. Because you have rejected knowledge, I also will reject you from being priest for Me; Because you have forgotten the law of your God, I also will forget your children.  “The more they increased, The more they sinned against Me; I will change their glory into shame.  They eat up the sin of My people; They set their heart on their iniquity.  And it shall be: like people, like priest. So I will punish them for their ways, And reward them for their deeds.  For they shall eat, but not have enough; They shall commit harlotry, but not increase; Because they have ceased obeying the LORD.
Matthew 22:23-32 NKJV
The same day the Sadducees, who say there is no resurrection, came to Him and asked Him,  saying: “Teacher, Moses said that if a man dies, having no children, his brother shall marry his wife and raise up offspring for his brother.  Now there were with us seven brothers. The first died after he had married, and having no offspring, left his wife to his brother.  Likewise the second also, and the third, even to the seventh.  Last of all the woman died also.  Therefore, in the resurrection, whose wife of the seven will she be? For they all had her.”  Jesus answered and said to them, “You are mistaken, not knowing the Scriptures nor the power of God.  For in the resurrection they neither marry nor are given in marriage, but are like angels of God in heaven.  But concerning the resurrection of the dead, have you not read what was spoken to you by God, saying,  ‘I am the God of Abraham, the God of Isaac, and the God of Jacob’? God is not the God of the dead, but of the living.”
1. Some people do not believe the Bible.
Luke 24:25-27 NKJV
Then He said to them, “O foolish ones, and slow of heart to believe in all that the prophets have spoken!  Ought not the Christ to have suffered these things and to enter into His glory?”  And beginning at Moses and all the Prophets, He expounded to them in all the Scriptures the things concerning Himself.
Hebrews 3:18-19 NKJV
And to whom did He swear that they would not enter His rest, but to those who did not obey?  So we see that they could not enter in because of unbelief.
2. Some people lack a desire to learn The Holy Scriptures.
1 Peter 2:1-3 NKJV
Therefore, laying aside all malice, all deceit, hypocrisy, envy, and all evil speaking,  as newborn babes, desire the pure milk of the word, that you may grow thereby,  if indeed you have tasted that the Lord is gracious.
3. Some people are too lazy to study The Scriptures. People make excuses and place the things of this world ahead of The Word of God. The things of this World are temporary and passing away. The Word of God stands for ever.
2 Timothy 2:14-16, 23-26 NKJV
Remind them of these things, charging them before the Lord not to strive about words to no profit, to the ruin of the hearers.  Be diligent to present yourself approved to God, a worker who does not need to be ashamed, rightly dividing the word of truth.  But shun profane and idle babblings, for they will increase to more ungodliness.  But avoid foolish and ignorant disputes, knowing that they generate strife.  And a servant of the Lord must not quarrel but be gentle to all, able to teach, patient,  in humility correcting those who are in opposition, if God perhaps will grant them repentance, so that they may know the truth,  and that they may come to their senses and escape the snare of the devil, having been taken captive by him to do his will.