What does Matthew 27:28 mean?

Matthew has written that all the soldiers in the battalion stationed at the governor's headquarters in Jerusalem have taken Jesus inside. Now they strip off the clothes He is wearing and drape a robe over His shoulders.

Much is made over the gospel accounts alternately describing the cloth as "purple" or as "scarlet" (Mark 15:17; John 19:5), as if this were a contradictory detail. It should be noted that color words can be vague, even in the modern world. Likewise, cultures don't assign individual words to a color unless they consider them notably different. Ancient peoples referred to the sea as "green," when modern people almost universally call the exact same colors "blue." The color "orange," likewise, was depicted as a shade of red or yellow until relatively recently. To ancient eyes, the difference in these terms is no more meaningful than modern debates over whether something is green-blue or blue-green.

Bible scholars suggest the robe was one of those worn by Roman military and civilian officials. The purpose is to dress Jesus in a deliberately silly caricature of a king. By giving Jesus a shoddy version of royal robe and crown, the soldiers can even more thoroughly mock Him for His "crime" of claiming to be the King of the Jews.