Two things that God hates are haughtiness and pride. They are actually two sides of the same sin - but nevertheless God really despises these things. We learn from this proverb that these two things are the very lamp that shines within the wicked - it is what they think gives them light and guidance. It should be a no brainer then why they are so blind to the things of God.
Haughty eyes are the first thing mentioned here. The word for haughty here means something having height - and actually refers to the physical height of the heavens. In the oriental culture it was considered a good thing to cast your eyes down before a superior. It showed respect. To this day orientals show their honor and deference to someone by bowing to them and lowering their eyes. Thus to have lifted eyes - even eyes raised to the heights - is to be a very disrespectful and arrogant person. It is a way of saying that you recognize no greater authority in life than yourself. Everyone else is "below" you.
A "proud heart" is also mentioned here. The word proud means something wide, spacious, and broad. When put with the word "heart" it came to mean someone arrogant - of a broad and prideful heart. One of the ways this speaks to us is that in biblical times someone who held a "broad" view of their morals and choices was someone who ignored the Scriptures and the Law - and chose rather to walk in the pride of their own desires (broad as they may be - yet still wrong!) rather than submit themselves to the Law of God and the boundaries it put on their actions and attitudes.
When a man has arrogant eyes that refuse any authority but their own, and a heart that refuses God's Law - that person is wicked. This proverb tells us that this is the "lamp" of the wicked - these arrogant eyes and proud heart. The lamp refers to the light by which this person seeks to live. The psalmist prayed, "Send forth Your light and Your truth, let them lead me." This was his request - that the light and the lamp that shone within him would be in agreement with God's Word - God's Law. Thus, as this light shone within him - he would see to know where to go and what to do. But for the wicked, their light is their own arrogance and pride. The light that guides them utterly rejects God's authority over their lives - and God's Word that speaks what is truth and light. The result is that their lamp shows darkness and not light. They are blind as a bat when it comes to any kind of vision or any kind of ability to walk in God's ways.
Oh, how we as believers need to reject in us eyes that are arrogant and lifted against God's authority in our lives. How we need to reject a heart that says that God's Word has nothing to say to us. If we want to be spiritually blind, these are the things we need to embrace - but if we want any kind of spiritual vision whatsoever - we need to reject anything that has to do with arrogance or prideful attitudes toward God or toward His Word.