The phrase "purple robe" typically symbolizes royalty, wealth, and power. It refers to a luxurious and prestigious clothing item, worn by kings and queens in the past. Full definition
Judges of the German Federal Courts wear purple robes with red lining, while judges of the Federal Patent Court wear black robes with blue vests. (jjmccullough.com)
A photograph from the St Paul's event captured five dancing bishops in long purple robes and made the Daily Telegraph! (premierchristianity.com)
The soldiers mocked him by pressing a crown of thorns on his head and putting a royal purple robe around him. (religion-online.org)