According to the contemporary poet Martial , Nero also held Nerva 's literary abilities in high esteem , hailing him as the " Tibullus of our time " . Another prominent member of Nero 's entourage was Vespasian , an old and respected general who had celebrated military triumphs during the 40s . It appears Vespasian befriended Nerva during his time as an imperial advisor , and may have asked him to watch over Vespasian 's youngest son Domitian when Vespasian departed for the Jewish war in 67 .