Definition and Nature:
Pride of heart, often referred to simply as "pride," is a condition of the human heart characterized by an inflated sense of one's own worth, abilities, or importance. It is considered a sin in Christian theology because it elevates the self above God and others, leading to a range of sinful behaviors and attitudes. Pride is often seen as the root of other sins, as it fosters a spirit of rebellion against God's authority and commands.

Biblical References:
The Bible addresses pride extensively, warning of its dangers and consequences. In Proverbs 16:18, it is written, "Pride goes before destruction, and a haughty spirit before a fall." This verse highlights the inevitable downfall that follows pride, emphasizing the self-destructive nature of this sin.

In the New Testament, James 4:6 states, "But He gives us more grace. This is why it says: 'God opposes the proud, but gives grace to the humble.'" This passage underscores the opposition between pride and humility, illustrating that God favors those who are humble and reliant on Him.

Examples in Scripture:
The Bible provides numerous examples of individuals who exhibited pride of heart and faced consequences as a result. One notable example is King Nebuchadnezzar of Babylon. In Daniel 4:30, he boasts, "Is this not Babylon the Great, which I myself have built by the might of my power and for the glory of my majesty?" His pride leads to his temporary downfall, as God humbles him by driving him away from human society until he acknowledges God's sovereignty.

Another example is found in the account of Lucifer, whose pride led to his fall from heaven. Isaiah 14:13-14 describes Lucifer's prideful ambition: "You said in your heart, 'I will ascend to the heavens; I will raise my throne above the stars of God; I will sit on the mount of assembly, in the far reaches of the north. I will ascend above the tops of the clouds; I will make myself like the Most High.'" This passage illustrates the ultimate consequence of pride—separation from God.

Theological Implications:
Pride of heart is fundamentally at odds with the Christian call to humility and submission to God's will. It is seen as a barrier to spiritual growth and a hindrance to one's relationship with God. The Bible consistently calls believers to cultivate humility, as seen in Philippians 2:3, which instructs, "Do nothing out of selfish ambition or empty pride, but in humility consider others more important than yourselves."

Practical Considerations:
Christians are encouraged to examine their hearts regularly for signs of pride and to seek God's help in cultivating humility. Prayer, confession, and accountability within the Christian community are vital practices in combating pride. Additionally, believers are urged to follow the example of Jesus Christ, who demonstrated ultimate humility by taking on human form and sacrificing Himself for humanity's redemption (Philippians 2:5-8).

Conclusion:
While pride of heart is a pervasive and destructive sin, the Bible offers hope through the transformative power of God's grace. By acknowledging one's dependence on God and embracing a life of humility, believers can overcome pride and live in accordance with God's will.