The apostle Paul answers this question and states the main reason why people choose not to believe in God: “And with all deception of unrighteousness in them that perish; because they received not the love of the truth, that they might be saved” (2 Thessalonians 2:10).
God gave His children ample evidence of His existence through His creative works in nature (Romans 1:20), in His written Word (2 Timothy 3:16-17), and in the life and death of Jesus Christ (John 3:16). Thus, people have every opportunity to get to know the truth and love it.
But people reject the truth simply because they don’t want it. They don’t love Christ who is the embodiment of “the truth” (John 14:6) and don’t wish to live by His principles of goodness. They don’t desire God to interfere with their way of life. For “… men loved darkness rather than light, because their deeds are evil” (ch. 1:19b).
In addition, the unbelievers don’t like their evil deeds to be exposed: “For everyone who does evil hates the Light, and does not come to the Light for fear that his deeds will be exposed” (John 3:20). Guilty offenders hate the judges who convict them of their wrong deeds, even though it’s not the judges’ fault. Likewise, sinners hate the Lord because He convicts them of breaking His law.
Sadly, those who hate the light of truth will be blinded by the devil (v. 19). Their refusal to cherish a love for the truth makes them susceptible to being influenced by all that is not truthful “that they should believe a lie” (2 Thessalonians 2:11).
But men are not left to their own sinful nature, God wants to heal people’s hearts through His Holy Spirit that grants a new nature that hungers and thirsts after righteousness. This is a free gift from God and is available to all that ask for it (Matthew 7:7).
After all what God did to save mankind, there is nothing more He can do to help them other than to respect their wishes and leave them to the course of their own choosing (Rom. 1:18, 24). For in love there is no forcing (Revelation 3:20).
In His service,