Cosplaying with death

In book 6 of the Aeneid, Virgil warns the reader in these terms:

'... facilis descensus Averno
noctes atque dies patet atri ianua Ditis;
sed revocare gradum superasque evadere ad auras,
hoc opus, hic labor est...' (4.126-31)

"The descent to Avernus [the Underworld] is easy;
the gate of Pluto stands open night and day;
but to retrace one's steps and return …