To him who is able to keep you from falling and to present you before his glorious presence without fault and with great joy -- to the only God our Savior, be glory, majesty, power and authority, through Jesus Christ our Lord, before all ages, now and forevermore! Amen (Jude 24-25).
There is a lot packed in this tiny book, warnings against the false teachers who had secretly slipped in among the believers to whom Jude was writing, clear descriptions of who they were and how they operated, and admonitions to contend for the faith and build yourselves up in you most holy faith. As his doxology affirms, Jude is convinced that our joyous victory is possible through the Lord Jesus Christ, even as strong forces in our midst are working agains the gospel.
Do you know who Jude was? He doesn't give us much to go on. He calls himself a servant of Jesus Christ and a brother of James. What he doesn't say is that this same James is a half-brother of Jesus, making Jude (sometimes referred to as Judas), also, a half-brother of Jesus! He and his brothers are identified by name in Matthew 13:55-56.
Once, when Mary and Jesus' brothers came to see him, someone in the crowd let him know. Jesus replied, "Who is my mother, and who are my brothers?" Pointing to his disciples he said, "Here are my mother and my brothers. For whoever does the will of my Father in heaven is my bother and sister and mother" (Matt 12: 46-50; see also Mark 3:31-32, Luke 8:19-20). Evidently Mary and his siblings did not exactly meet his definition of family.
In fact, we are told outright that his own brothers did not believe in him (John 7:5).
So what happened to change Jude from a doubter to a believer? How is it that he now says of his brother Jesus Christ our Lord, before all ages, now and forevermore! It was the resurrection! Jesus, the brother they couldn't figure out, the one who changed everything up and created scenes in public -- had conquered death!
No wonder Jude included this exhortation in his letter: Be merciful to those who doubt (22). He, of all people, would know that doubting need not be terminal. Doubters abound, but so does God's power to get our attention. For some, doubt will turn to faith when the doubter is convinced intellectually of the validity of the gospel through a book maybe, or a presentation, or a discussion. But for others, the love and gentleness of a child of God will be the proof the doubter needs to turn to Christ.
We don't know what goes on in other people's minds, and we don't know what God will use to turn doubters into believers. But we know that he loves doubters and wants them to respond to the truth of the gospel. Do not despise doubters; do not lose hope that they will ever come to faith. Bring them in prayer to Jesus, who lived with a houseful of doubters. Let his resurrection power shine through your life as you live before them. Be merciful, as God has been merciful to you.
Who knows how the Lord plans to use the one who struggles with doubt before taking hold of faith, but if Jude is any indication, I'd say we have every reason for hope!