That happened to me recently. I've been reading through Isaiah again over Christmas break. Now, if you know the story of the Garden of Eden, you're probably aware of God's words to Adam:
"Cursed is the ground because of you; through painful toil you will eat food from it all the days of your life. It will produce thorns and thistles for you, and you will eats the plants of the field. By the sweat of your brow you will eat your food until you return to the ground, since from it you were taken; for dust you are and dust you will return." (Gen. 3:17-19) Thorns are a key reminder of God's judgment and the curse that results from our sin.
This connection between thorns and God's judgment are all over the place in Isaiah. Israel was intended to be an abundant vineyard, but instead they produced bloodshed. The result? God says, "I will make it a wasteland, neither pruned or cultivated, and briers and thorns will grow there" (Is 5:6). God will use Assyria to judge Israel so that "where there were a thousand vines worth a thousand silver shekels, there will be only briers and thorns" (7:23). The people are called to lament for "the land of my people, a land overgrown with thorns and briers" (32:13), for "the peoples will be burned to ashes; like cut thornbushes they will be set ablaze" (Is. 33:12). God's judgment is also declared against Edom in the same way: "Thorns will overrun her citadels, nettles and brambles her strongholds..." (34:13).
Thorns are a sign of God's curse, God's judgment on sin and sinners. The crown of thorns is a visual summary of the Suffering Servant of Is. 52:13-53:12. He bears the curse so that others might be blessed. The Good Shepherd suffers slaughter so that his sheep might live. He was numbered among the transgressors so that we might be numbered among those declared righteous. This Root was cut off so that we might be grafted on.
And so judgment is not the last word in Isaiah. Isaiah holds out hope, for the true Vine, a shoot from the stump of Jesse (11:1) who was crushed for our iniquities and wounded for our transgressions. It is fitting, then, that this King of the Cursed wore a crown of thorns as he himself was buried in the ground for our sakes. And yet the thorns were no match for the powerful Root who, after returning to the ground, returned again to life, causing the very trees of the field to applaud him as the One who forever casts out the thorns and briers (Is 55:12). And this Root grafts us into himself so that a song is raised of a fruitful vineyard which will fill all the world with fruit (Is 27:6).
So next time you think of Jesus' crown of thorns, remember that he bore the curse so that we might bear fruit as we abide in him. We can do this because, although sin brought the curse of thorns on our toil, the resurrection of Jesse's Root brought new life and blessing, in which our labor is not in vain (Is 65:23; 1 Cor. 15:58).