Bede the Venerable
Catena Aurea · Johannesevangelium 19
Then Pilate therefore took Jesus, and scourged him. And the soldiers platted a crown of thorns, and put it on his head, and they put on him a purple robe, And said, Hail, King of the Jews! and they smote him with their hands. Pilate therefore went forth again, and saith unto them, Behold, I bring him forth to you, that ye may know that I find no fault in him. Then came Jesus forth, wearing the crown of thorns, and the purple robe. And Pilate saith unto them, Behold the man!
For instead of a diadem, they put upon Him a crown of thorns, and a purple robe to represent the purple robe which kings wear. Matthew says, a scarlet robe, (Mat. 27:28) but scarleta and purple are different names for the same colour. And though the soldiers did this in mockery, yet to us their acts have a meaning. For by the crown of thorns is signified the taking of our sins upon Him, the thorns which the earth of our body brings forth. And the purple robe signifies the flesh crucified. For our Lord is robed in purple, wherever He is glorified by the triumphs of holy martyrs.