In the sermon titled 'Clip: Jude 3-4 (LSB)' by David Green, the speaker discusses the importance of contending earnestly for the faith that has been handed down to the saints. Initially, the speaker intended to write about the common salvation but felt compelled to address the necessity of defending the faith. He warns of certain ungodly individuals who have infiltrated unnoticed, turning God's grace into sensuality and denying Jesus Christ as the only Master and Lord. These individuals were marked for condemnation. The sermon emphasizes vigilance and the defense of the faith against such corrupt influences.

Beloved, verse 3, Beloved, while I was making every effort to write you about our common salvation, I felt the necessity to write to you exhorting that you contend earnestly for the faith which was once for all handed down to the saints. For certain persons have crept in unnoticed, those who were long beforehand marked out for this condemnation, ungodly persons who turned the grace of our God into sensuality and deny our only Master and Lord, Jesus Christ.