Jude 4 For certain men have crept in unnoticed, who long ago were marked out for this condemnation, ungodly men, who turn the grace of our God into lewdness and deny the only Lord God and our Lord Jesus Christ.
Jude’s indictment of these men begins with this verse. He says that certain men have crept into the church unnoticed. The image Jude is attempting to portray is one of stealth and secrecy. They did not come boldly, but slipped in like the wedding guest in the parable Jesus told, who was found without a proper garment, Matthew 22:11-13. In fact, this passage in Matthew corresponds quite well with the content Jude is addressing.