Contend Earnestly for the Faith
This passage contains the apostle Jude's exhortation to believers to hold firmly to the truth of the faith and fight for it. Jude stresses that believers must live out the uncorrupted gospel the apostles delivered just as it is, without mixing in their own thoughts or feelings. He also warns that when believers fall to Satan's temptations and choose sin, it is not a simple mistake but a conscious choice, so repentance does not come easily and recovery is hard.
The sermon leads us to consider whether believers' hearts have received God's grace and become good soil, or whether they are rocky ground where thorns and thistles grow because of worldly greed and lust. In particular, it points out that conviction about the Word and discernment are essential to protect our souls from false teachers who have slipped into the church and twist the truth, and from the temptations of heresy. Since Satan attacks relentlessly to make believers fall, it says that believers must not let their guard down but stay awake and be led by the Holy Spirit.
The sermon warns that if believers do not contend earnestly for the faith, their salvation can be taken from them. It also reminds us that false truth is a well without water that gives no spiritual satisfaction, and asks us to stand firm in the Word so that the Holy Spirit can be a strong fence around us. Finally, it leads us to reflect on how believers can keep the faith to the very end without being shaken by Satan's schemes.