The Christianity that was “common” in Jude’s day was the kind for which every believer was exhorted to “contend.” Believers were to struggle to maintain their faith. They were to make an all out effort (“earnestly”) to preserve a pure faith for the next generation. The faith was an unchanging faith (“once for all delivered”) that affirmed “our only Master and Lord, Jesus Christ.” Believers were to struggle because there were those who “crept in” with a brand of Christianity that tolerated “ungodly” and self-indulgent living. These false believers (“condemnation”) also “reject authority” and “cause divisions” and are referred to as “grumblers.”
True believers are exhorted to “keep themselves in the love of God,” something which requires much effort and sacrifice, along with “praying in the Holy Spirit.” Beloved, let us not hand the next generation a shabby faith that only seeks its own comfort and convenience, but let us keep our faith true to God’s Word!