Quoting Richard Sibbes:
This bruising is required before conversion that so the Spirit may make way for himself into the heart by leveling all proud, high thoughts, and that we may understand ourselves to be what indeed we are by nature. We love to wander from ourselves and to be strangers at home, till God bruises us by one cross or other, and then we `begin to think’, and come home to ourselves with the prodigal (Luke 15:17). It is a very hard thing to bring a dull and an evasive heart to cry with feeling for mercy. Our hearts, like criminals, until they be beaten from all evasions, never cry for the mercy of the judge.
Again, this bruising makes us set a high price upon Christ. Then the gospel becomes the gospel indeed; then the fig leaves of morality will do us no good. And it makes us more thankful, and, from thankfulness, more fruitful in our lives; for what makes many so cold and barren, but that bruising for sin never endeared God’s grace to them?
Likewise this dealing of God establishes us the more in his ways, having had knocks and bruisings in our own ways. This is often the cause of relapses and apostasy, because men never smarted for sin at the first; they were not long enough under the lash of the law. Hence this inferior work of the Spirit in bringing down high thoughts (2 Cor. 10:5) is necessary before conversion. And, for the most part, the Holy Spirit, to further the work of conviction, joins with it some affliction, which, when sanctified, has a healing and purging power. ~ The Bruised Reed by Richard Sibbes