I recently came across an answer to this question that I honestly don’t think I’ve heard before. At it’s come from John Piper’s recent book ‘Providence’:
‘There are, no doubt, countless wise and holy reasons God plans to permit sin…[one of these is] that God’s ultimate aim in creation and providence is to display the glory of His grace, especially in the suffering of Christ, echoing forever in the all-satisfying praises of the redeemed. That is the ultimate wise, just and good purpose of God in planning to permit the fall.’ (page 177).
Let’s break this up a little.
If God ‘chose us in [Christ] before the creation of the world to be holy and blameless in His sight’ (Ephesians 1:4). And if ‘this grace was given to us in Christ Jesus before the beginning of time’ (2 Timothy 1:9). And if our names were (or were not) ‘written from the creation of the world in the book of life’ (Revelation 13:11). Then we must concede that God had already purposed for Jesus to die for sin before sin even existed!
Therefore, of the reasons God planned to permit to sin and suffering, is so that we might be saved by the suffering of Jesus for our sin and then rejoice and delight in God. In this way it was not only justice that moved God to appoint suffering as the consequence of sin, but it was also mercy. Because it is by the suffering of Jesus that we are saved.
Perhaps one application for this, is that we might more willingly be able to praise God in suffering. Because it reminds us of the hope which Jesus has purchased for us.
I think of Genesis 50:20: ‘As for you, you meant evil against me, but God meant it for God’. Piper argues that we might equally be able to say… “as for you, Adam and Eve, you meant it for evil, but God meant it for good. Your purpose in sinning was the vain pursuit of pleasure through self-exalting autonomy. God’s purpose in permitting your sin was to give His people the pleasure of seeing and savouring the glory of His grace in the inexpressible suffering and triumphs of His Son”.