Gnosticism predates Christianity and even Judaism by thousands of years. It wasn't Christ they embraced it was the perception of some new special knowledge shared by Christ that they sought, not unlike the Reformation and its narrow interpretation of Scripture.
It's actually interesting that they talk so much about 'salvation'. Just as one might be admitted to the mysteries to be given the secret knowledge which would lead to immortality, they focus on being saved. It's the ultimate tit-for-tat. And they encourage this manipulative attitude. It's "if you died right now, would you be saved?" It's "What's in it for me?" as the primary motivation for Christianity.
I don't think that's what's in their hearts, but it's certainly what's in their words.