Dean Merivale remarks (chapter li.) on this passage, that in the despair of another life which pervaded Paganism at the time, the Roman was exasperated at the Druids' assertion of the transmigration of souls.

But the passage seems also to betray a lingering suspicion that the doctrine may in some shape be true, however horrible were the rites and sacrifices.

The reality of a future life was a part of Lucan's belief, as a state of reward for heroes.

(See the passage at the beginning of Book IX.; and also Book VI., line 933).

But all was vague and uncertain, and he appears to have viewed the Druidical transmigration rather with doubt and unbelief, as a possible form of future or recurring life, than with scorn as an absurdity.
(20) Plutarch says the Consuls fled without making the sacrifices usual before wars.