Fear of how grace will change you

“Curiously enough, it is a fear of how grace will change and improve them that keeps many souls away from God. They want God to take them as they are and let them stay that way. They want Him to take away their love of riches, but not their riches—to purge them of the disgust of sin, but not of the pleasure of sin. Some of them equate goodness with indifference to evil and think that God is good if He is broad-minded or tolerant about evil. Like the onlookers at the Cross, they want God on their terms, not His, and they shout, “Come down, and we will believe.” But the things they ask are the marks of a false religion: it promises salvation without a cross, abandonment without sacrifice, Christ without his nails. 

God is a consuming fire; our desire for God must include a willingness to have the chaff burned from our intellect and the weeds of our sinful will purged. The very fear souls have of surrendering themselves to the Lord with a cross is an evidence of their instinctive belief in His Holiness. Because God is fire, we cannot escape Him, whether we draw near for conversion or flee from aversion: in either case, He affects us. If we accept His love, its fires will illumine and warm us; if we reject Him, they will still burn on in us in frustration and remorse.”

― Fulton J. Sheen, Peace of Soul: 

Timeless Wisdom on Finding Serenity and Joy by the Century's Most Acclaimed Catholic Bishop