Why don’t unbelievers believe the gospel and be saved? Here are three reasons directly from Scripture.

1. “But a natural man does not accept the things of the Spirit of God, for they are foolishness to him; and he cannot understand them, because they are spiritually appraised” (1Co 2:14).

A natural man cannot take, receive, accept, or welcome spiritual things from God. He rejects the spiritual implications of the gospel message, refusing to seize it and act upon it. The unbeliever absolutely does not have the power to understand the things of God or know them experientially.

2. “The god of this world has blinded the minds of the unbelieving so that they might not see the light of the gospel of the glory of Christ, who is the image of God” (2Co 4:4).

God allows unbelievers to be blinded by Satan (the god of this world) for the purpose of preventing them from seeing or understanding the gospel. That phrase “has blinded” is an imperfect Greek verb, meaning that the blinding by Satan is a past tense and an active on-going spiritual blindness. It cannot be remedied without divine intervention from God. No one can remove the blinders from his own eyes.

3. “He has blinded their eyes and He hardened their heart, so that they would not see with their eyes and perceive with their heart, and be converted and I heal them” (John 12:40).

When God hardens hearts of unbelievers it is a judicial hardening; they have already turned from the light to walk in darkness. When men refuse to obey the gospel and persist in their love of sin, God can choose to harden their hearts even further as an act of judgment against them. God did this in the case of Pharaoh. Every time he refused to let Israel go from slavery in Egypt, God judicially hardened his heart (Exo 4:21-22). These types of men begin by not believing, and then God makes it so that they cannot believe.

In each of the three cases above it can be seen that unregenerate man does not have the ability to believe by his own will and be saved. God is the One who calls to salvation, and when He does, that person will unfailingly come to Christ (John 6:37). He will then rejoice in the faith that God has given to him! (Eph 2:8).