Here is a question that I answered recently, which I thought might be helpful to some who have had the same question or one of a similar nature. The first paragraph is the question that I received and the last two are my answer.
“I was doing some reading through the books of Matthew and Mark and I found a discrepancy in their accounts of the soldier’s treatment of Christ before the Crucifixion. In Matthew 27:27-31 he states the robe the soldiers put around him was red or Scarlett, but in Mark 15:16-20 he states that the robe was purple. The Strong’s numbers are 4209 (Mark) and 2847 (Matthew). I am still a little confused after looking it up.”
Great question, and while I may not can totally resolve everything about this, I pray the following will help. It appears that both happened. The Roman soldiers wore cloaks that were of a reddish color, which many times bespeak of war and or evil in Scripture; this was mocking Jesus who is the prince of peace and his sinless character. The purple color was often associated with royalty thus mocking his kingship. Although they surely clothed him with these garments as well as the crown of thorns in mockery, He really is the one who took the evil of the world upon himself, and He is the king of kings.
Let me mention a few other things, which may help; first, these colors are often found together (Revelation 17:3-4) and are different from red (Revelation 6:4, 12:3); second, it is not necessarily red or purple—as we think of; third, “the ancients did not discriminate among colors as closely as we do” ((Expositors Bible Commentary in loc)) fourth, the color to us would have been more of “reddish purple” ((New American Commentary in loc)). The BAGD ((Bauer, Arndt, Gingrich, and Danker p694)) mentions a reference where the solders cloak is said to be purple; lastly, by the Holy Spirit mentioning both colors, the full breadth of the cruel mocking is highlighted. I hope this helps.