What do people fear in Jude 1:23?

I know *fear* can mean multiple things. But what I'm getting out of Jude 1:23 is that people saved others by fearing something. Do they fear Satan? Or do they fear God? The whole time, I was assuming fear was a bad thing. > **1**20 But ye, beloved, building up yourselves on your most holy faith, praying in the Holy Ghost, 21 keep yourselves in the love of God, looking for the mercy of our Lord Jesus Christ unto eternal life. 22 And of some have compassion, making a difference: 23 and **others save with fear,** pulling them out of the fire; hating even the garment spotted by the flesh. > > [[KJV](http://www.biblegateway.com/passage/?search=Jude+1%3A20-23&version=AKJV)] my emphasis