The ancient editor Porphyrion read the first six odes of this book as a single sequence, one unified by a common moral purpose and addressed to all patriotic citizens of Rome. These six "Roman odes", as they have since been called (by HT Plüss in 1882), share a common meter and take as a common theme the glorification of Roman virtues and the attendant glory of Rome under Augustus. Ode III.2 contains the famous line "Dulce et decorum est pro patria mori," (It is sweet and honorable to die for one's country). Ode III.5 "Caelo tonantem credidimus Jovem" makes explicit identification of Augustus as a new Jove destined to restore in modern Rome the valor of past Roman heroes like Marcus Atilius Regulus, whose story occupies the second half of the poem.