Jude 4 on the reprobates

Jude 4 says that there were certain men who crept in unawares, who were ordained of old to the condemnation, these men we are told turn the grace of God into lasciviousness.
The question is what does this mean? Those who, like Catholics, labeling themselves reformed, teach that we are saved by grace alone but this grace is infused unto us so that we work. Of course, this means according to them that if you are not working you have serious reasons to doubt whether you're saved.

However, the verse in question doesn't so much hint that these men lacked evangelical works. Another said set of verses used to attack the truth of free and unconditional grace is Matthew 7 but with clear study of the passage hardly speaks against such. But as far as this verse in Jude goes these men turn the grace of God into lasciviousness. They take the unadulterated gospel of Christ and they do not believe it but rather they disbelieve it. These men therefore disbelieve the truth and so therefore they turn the grace into lasciviousness. Other verses that present this is found in Romans 2:4-5. The mistake by the many so-called Calvinist today is that God is patient with both the elect and reprobate and so therefore wants both to be saved. This is far from the facts as say Proverbs 16:4 says that the reprobates are made for destruction and that they are like natural brute beast as 2 Peter 2:12 says.
For God he is patient with the elect alone not wanting any to perish but that all to come to the knowledge of the truth. For the sake of the elect is God longsuffering towards the reprobate.