Maintaining joy in God takes 'work'; that is, it's a fight against every impulse for alien joys and every obstacle in the way to seeing and savoring Christ.
John PiperThe ultimate difference between God's wisdom and man's wisdom is how they relate to the glory of God's grace in Christ crucified. God's wisdom makes the glory of God's grace our supreme treasure. But man's wisdom delights in seeing himself as resourceful, self-sufficient, self determining, and not utterly dependent on God's free grace.
John PiperIf God were not just, there would be no demand for his Son to suffer and die. And if God were not loving, there would be no willingness for his Son to suffer and die. But God is both just and loving. Therefore his love is willing to meet the demands of his justice.
John PiperThe way of the cross is the way of suffering. Christians are called to die, not kill, in order to show the world how they are loved by Christ.
John PiperAll the different ways God has chosen to display his glory in creation and redemption seem to reach their culmination in the praises of his redeemed people. God governs the world with glory precisely that he might be admired, marvelled at, exalted and praised. The climax of his happiness is the delight he takes in the echoes of his excellence in the praises of the saints.
John Piper