John Gill Commentary Mark 15:20

"And when they had mocked him, they took off from him the purple, and put on him his garments. And they lead him out to crucify him." — Mark 15:20 (ASV)

And when they had mocked him
To their satisfaction, and had had enough of this sort of diversion:

they took off the purple from him ;
and so, in their way, unkinged him;

and put his own clothes on him :
both that he might be known to be the same person; and that the four soldiers, who had the charge of him, might have the perquisites of his clothes at his execution:

and led him out to crucify him :
they led him out of the "praetorium", or judgment hall, and through the city, without the gates of it, to the usual place of crucifixion; he bearing his own cross, when first led out.