The history of having folks stomp on something with Jesus writte on it was popular in Tokugawa Japan ~ they'd approach someone they thought had become a Christian and challenge them to step on the medallion with Jesus' name. If they refused they take them out and crucify them.
The professor undoubtedly understood this ~ so he'd know it was a DEATH THREAT punishable under Florida statutes 836-10 as a second degree felony.