“Vital documents about the rebel state of mind were ignored until after the Rebellion because they used terms in Latin, the secret cant of the Christians, unintelligible to non-believers. Biblical allusions in rebel correspondence and rhetoric sailed completely over the heads of their enemies. Jerome Amakusa held his army together through a long siege that lasted through Lent 1638, only to discover that his most trusted lieutenant was plotting to betray him on Easter Sunday. This irony escaped the notice of the government troops, who did not know what Easter Sunday was.”

From Christ’s Samurai: The True Story of the Shimabara Rebellion.