Charles Ellicott Commentary Matthew 27:29

"And they platted a crown of thorns and put it upon his head, and a reed in his right hand; and they kneeled down before him, and mocked him, saying, Hail, King of the Jews!" — Matthew 27:29 (ASV)

A crown of thorns — The word is too vague for us to identify the plant with certainty, but most writers have settled on the Zizyphus Spina Christi, known locally as the Nebk. This shrub grows abundantly in the Jordan valley and has pliable, flexible branches, sharp prickly thorns, and dark, glossy green leaves, like ivy. The resemblance of a crown made from it to the garlands worn by conquering kings and emperors made it perfectly suited for their purpose. The shrub was very likely to be found in the garden attached to the Praetorium.

A reed in his right hand — Similarly, the word here is vague; it may have been the stalk of a sugar-cane, a Papyrus, or an Arundo. It represented, of course, the scepter. Even under the Republic, generals had wielded a scepter in their triumphs, and under the Empire, it had become the accepted symbol of sovereignty, as it was for Greek and Eastern kings.

They bowed the knee before him — We must picture the entire cohort joining in the mocking homage. The term used in Mark 15:19 implies a continuous act, not a momentary one—the soldiers filing past the mock-king and kneeling as they went.