Jollyblogger has at long last finished his series on the five points of Calvinism with point five: Perseverance of the Saints. He explains that it has two components:
1. Someone who is genuinely saved cannot lose that salvation.
2. Only those who persevere in faith until the end will be saved.
Some Arminians deny the first point because they think the second requires denying it. The result is legalism. Some dispensationalists, such as Zane Hodges (and to a lesser degree Charles Ryrie) deny the second because they believe the first requires doing so. The result is antinomianism. Both deny plain statements in the Bible, which Jollyblogger lists. I've argued for exactly the same thing here.
Update: He's now got a post up linking to all the entries in the series.