Here is a dilemma for them. They say "keeping on believing is not a work."
OK.
Notice this: Jesus answered them, “This is the work of God, that you believe in him whom he has sent.” John 6:29.
So here we have this:
1) Jesus here is either saying that to believe in God is a work man must do. This would then prove that believing is actually a work. Therefore to believe in God is then to do the works of God, as some put it, in other words it is a work.
-or-
2) Jesus is showing that in order for a person to believe, that is, to have supernatural faith is an act, or work of God Himself in the believer.
This blows apart their theory in two ways, and shows their teaching unbiblical on both accounts:
a. Believing would be a work according to their teaching and how they perceive what Jesus stated. They must take this as such because of their belief in free will. So the person did the believing here and it is then a work, it is doing the work of God.
b. Jesus is destroying the free will decision based belief and showing that faith is a gift, and that a person believing unto salvation is a work of God in man, not a work of man.
Now there will much wresting of this. Some will attempt to say they believe the latter of the 2, but they've been preaching believing is a decision all along, something that man does, making it by necessity a work.