The formation of the life of a person in the womb is the work of God, and it is not merely a mechanical process but a work on the analogy of weaving or knitting: "Thou didst knit me together in my mother's womb" (psalm 139:13). The life of the unborn is the knitting of God, and what He is knitting is a human being in His own image, unlike any other creature in the universe... The destruction of conceived human life - whether embryonic, fetal, or viable - is an assault on the unique person-forming work of God.
John PiperSo 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 PiperWe have brought nothing into the world, so we cannot take anything out of it either.' There are no U-Hauls behind hearses.
John PiperThe deepest need that you and I have in weakness and adversity is not quick relief, but the well-grounded confidence that what is happening to us is part of the greatest purpose of God in the universe - the glorification of the grace and power of his Son - the grace and power that bore Him to the cross and kept him there until the work of love was done.
John Piper