So saving grace, converting grace, for Augustine, is God's giving us a sovereign joy in God that triumphs over all other joys and therefore sways the will. The will is free to move toward whatever it delights in most fully, but it is not within the power of our will to determine what that sovereign joy will be.
John PiperIt is evil to justify killing (unborn babies) by the happy outcome of eternity for the one killed. This same justification could be used to justify killing one-year olds, or any heaven-bound believer for that matter. The Bible asks the question: "Shall we sin that grace may abound?" (Romans 6:1) And: "Shall we do evil that good may come?" (Romans 3:8). In both cases the answer is a resounding NO. It is presumption to step into God's place and try to make the assignments to heaven or to hell. Our duty is to obey God, not to play God.
John PiperSuffering in the path of Christian obedience, with joy - because the steadfast love of the Lord is better than life (Psalm 63:3) - is the clearest display of the worth of God in our lives. Therefore, faith-filled suffering is essential in this world for the most intense, authentic worship. When we are most satisfied with God in suffering, he will be most glorified in us in worship. Our problem is not styles of music. Our problem is styles of life. When we embrace more affliction for the worth of Christ, there will be more fruit in the worship of Christ.
John PiperThe inner essence of worship is cherishing Christ as gain - indeed as more gain than all that life can offer - family, career, retirement, fame, food, friends. The essence of worship is experiencing Christ as gain. Or to use words that we love to use around here: it is savoring Christ, treasuring Christ, being satisfied with Christ.
John Piper