Definition:
Spiritual blindness refers to the inability or unwillingness to perceive and understand spiritual truths. It is a condition where individuals are unable to see or comprehend the things of God, often due to sin, unbelief, or the influence of the world and Satan.

Biblical References:
The concept of spiritual blindness is addressed throughout Scripture, highlighting both its causes and consequences. In the Old Testament, the prophets frequently spoke against the spiritual blindness of Israel. Isaiah 6:9-10 records God's commission to Isaiah: "Go and tell this people: ‘Be ever hearing, but never understanding; be ever seeing, but never perceiving.’ Make the hearts of this people calloused; deafen their ears and close their eyes. Otherwise they might see with their eyes, hear with their ears, understand with their hearts, and turn and be healed."

In the New Testament, Jesus often confronted spiritual blindness among the religious leaders of His day. In Matthew 15:14 , He describes the Pharisees as "blind guides," warning that "if a blind man leads a blind man, both will fall into a pit." Similarly, in John 9:39-41 , after healing a man born blind, Jesus declares, "For judgment I have come into this world, so that the blind may see and those who see may become blind." The Pharisees, questioning their own blindness, are told by Jesus, "If you were blind, you would not be guilty of sin; but now that you claim you can see, your guilt remains."

Causes of Spiritual Blindness:
1. Sin and Unbelief: Sin hardens the heart and clouds spiritual perception. In 2 Corinthians 4:4 , Paul explains, "The god of this age has blinded the minds of unbelievers, so that they cannot see the light of the gospel of the glory of Christ, who is the image of God."

2. Pride and Self-Righteousness: The Pharisees' spiritual blindness was largely due to their pride and self-righteousness. They believed they had spiritual insight, yet they failed to recognize Jesus as the Messiah.

3. Worldly Influences: The distractions and temptations of the world can lead to spiritual blindness. In 1 John 2:11 , it is written, "But whoever hates his brother is in the darkness and walks in the darkness. He does not know where he is going, because the darkness has blinded his eyes."

Consequences of Spiritual Blindness:
Spiritual blindness results in a separation from God and an inability to understand His will and purpose. It leads to a life devoid of true spiritual insight and often results in judgment, as seen in the warnings given by Jesus and the prophets.

Remedy for Spiritual Blindness:
The remedy for spiritual blindness is found in turning to Christ, who is the Light of the World. In John 8:12 , Jesus proclaims, "I am the light of the world. Whoever follows Me will never walk in the darkness, but will have the light of life." Repentance, faith in Christ, and the work of the Holy Spirit are essential for gaining spiritual sight. Ephesians 1:18 expresses a prayer for believers: "I ask that the eyes of your heart may be enlightened, so that you may know the hope of His calling, the riches of His glorious inheritance in the saints."

Conclusion:
Spiritual blindness is a significant theme in the Bible, illustrating the human condition apart from God's revelation and grace. Through Christ, the blind can receive sight, and those in darkness can walk in the light.