“God gave them a spirit of stupor, 

eyes that would not see 

and ears that would not hear, 

down to this very day.”

The quotation is from Isaiah 29:10 as used by the Apostle Paul in Romans 11:8. For those who have been around church and heard teaching from the Bible again and again, yet failed or refused to do anything about it, this verse is a stern and fearful warning. The more you hear and fail to respond, the harder your heart will become.

In Mark’s Gospel Jesus quotes from Isaiah (6:9-10), which has a similar meaning.

^“And he said to them, ‘To you has been given the secret of the kingdom of God, but for those outside, everything comes in parables; in order that “they may indeed look, but not perceive, and may indeed listen, but not understand; so that they may not turn again and be forgiven.”‘”

This passage uses hyperbole. To quote FF Bruce, it demonstrates “the Hebrew tendency to express a consequence as though it were a purpose….” It means, in effect: “Go and deliver my message, but don’t expect them to pay any attention to it. The effect of your preaching will be their persistent refusal to accept what you say, to the point where they will have rendered themselves incapable of accepting it.”  (Bruce, The Hard Sayings of Jesus, p. 100)

In his foreknowledge God realizes who will reject his word when it is preached, which is why these prophetic expressions seem to be God’s purpose, rather than consequences of personal human response. While we rightly think of those in Christian lands as being blessed because of the many benefits afforded them by virtue of a historically dominant Christian ethic, there is also a downside. Those who hear the Gospel again and again but fail to believe it become calloused to the things of God. Jesus taught using parables for many reasons, but one was so that unbelievers wouldn’t understand. However, parables are memorable, and not just for the faithful who do understand. Even an unbeliever will remember the story, and if that person becomes interested in pursuing faith at a later time, the Holy Spirit, who is at work within their heart will give them understaning concerning the parable.

God doesn’t capriciously choose to make some people receptive and harden the hearts of others. Rather, it is the willingness or unwillingness on the part of each individual to pay attention and believe, or reject and disbelieve God’s Word that results in a harder or more receptive heart. Those who choose not to believe will become increasingly insensitive to God’s Word when it is preached. “They trip over the stumbling stone, as they were destined to do” (1 Peter 2:8). In other words, unbelievers will naturally stumble over the Gospel of Christ, because being offended by Jesus is the natural destiny of those refuse to believe God’s Word, and who disobey its plain teaching. We see this regularly in our world today.

The more you listen and fail to heed, the less you will be able to hear, understand and remember. Call this spiritual Alzheimers. Dementia and Alzheimers may be slowed by persistently exercising your brain: read and write regularly, solve puzzles, think! Physical exercise helps slow this process as well. Mental and physical inactivity allows the brain to die. The same may be said of the spiritual: we need to exercise by listening, studying, memorizing and above all obeying the Word of God.

Jesus said, “Pay attention to what you hear: with the measure you use, it will be measured to you, and still more will be added to you. For to the one who has, more will be given, and from the one who has not, even what he has will be taken away.”
The Holy Bible: English Standard Version. Wheaton: Standard Bible Society, 2016. (Mark 4:24-25).

The more attention you pay, the more that investment pays dividends of further revelation from God. The less attention you pay, the less you will understand, or care to. Eventually, your lack of faith will result in great loss. What you once knew will be in doubt to such a degree that you forget it. You will become spiritually insensitive and replace that with sensuality. “Having lost all sensitivity they have given themselves over to sensuality, so as to indulge in every kind of impurity with a continual lust for more” (Ephesians 4:19, NIV). Sensuality may take the form of sexual immorality, pleasure or thrill seeking, and drug or alcohol addiction. All this because you failed to pay attention to the Word of God and believe what you heard.