The text you provided is a portion of the Epistle of Jude, a short letter written by Jude, the brother of James, and addressed to the early Christian churches. Here are some ways you can apply the teachings and principles found in this text to your life:

Contending for the Faith: Jude emphasizes the importance of earnestly contending for the faith that was once delivered to the saints (verse 3). This means standing firm in our Christian beliefs and defending the core doctrines of the faith. We can apply this by being well-grounded in our understanding of Scripture, discerning truth from error, and boldly sharing our faith with others.

Beware of False Teachers: Jude warns about the presence of false teachers and their destructive influence (verses 4, 8, 10). These individuals twist God's grace to justify immorality and deny the authority of Jesus Christ. We can apply this warning by being vigilant, discerning, and testing all teachings against the truth of Scripture. We should also be cautious about whom we follow and listen to, ensuring they align with biblical teachings.

Remembering God's Judgment: Jude reminds his readers of God's judgment on the ungodly in the past, such as the destruction of those who left Egypt (verse 5) and the punishment of the angels who sinned (verse 6). We can apply this by recognizing that God is just and will ultimately hold everyone accountable for their actions. This should motivate us to live righteous lives and share the gospel with others so that they, too, can escape God's judgment through faith in Christ.

Showing Mercy and Compassion: Jude encourages his readers to show mercy and compassion to those who are struggling or deceived (verse 22). While we stand firm in our faith, we should also be compassionate and gracious toward those who are lost or misled. We can reach out to those who are wandering, offering them guidance and support, and praying for their salvation.

Building Ourselves Up in the Faith: Jude exhorts his readers to build themselves up in their most holy faith, praying in the Holy Spirit (verse 20). We can apply this by actively growing in our relationship with God through prayer, Bible study, fellowship with other believers, and obedience to God's Word. By doing so, we strengthen our faith and become more resilient in the face of trials and temptations.

Keeping Ourselves in God's Love: Jude encourages his readers to keep themselves in the love of God (verse 21). This means maintaining a close relationship with God and abiding in His love. We can do this by obeying His commandments, loving others, and seeking to live a life that pleases Him. As we remain in God's love, we experience His mercy, grace, and eternal life.

Glorifying God: The epistle concludes with a doxology, ascribing glory, majesty, dominion, and power to God (verse 25). We can apply this by recognizing God's sovereignty and majesty in our lives. Let our lives be a testament to His glory, and may our actions and words bring honor to His name.

By heeding the warnings, instructions, and encouragements found in this text, we can live faithful, discerning, and purposeful lives as followers of Christ.