St. Dorotheus of Gaza says there are two kinds of fear: one is the kind of fear that a beginner has and the other the kind of fear that a Saint has. The first person [the beginner] fears God because he is afraid of hell, he is afraid of punishment, he is afraid that at the end of days, he’ll be cast into darkness.
The other Saint fears God because he seeks to please God because he loves Him. The fear is not of somebody being afraid of some kind of punishment, but because somebody has tasted the sweetness of God, the sweetness of being with God, and because of that, fears losing his relationship with God. St. Dorotheus of Gaza calls this the perfect fear: not a fear of punishment—not a fear of hell, but a fear of upsetting the one he loves.
—Fr. Daniel Fanous
Fear God, but don’t be afraid