Naḥum Ish Gam Zo always believed that whatever happened was for the best.
The Gemara relates that once the Jewish community needed to send a tribute to the Caesar, and they decided to send it with Naḥum Ish Gam Zo since he was someone for whom miracles occurred. When stopping on his trip, he was queried in the inn regarding his mission and he admitted that he was bringing a tribute to the Caesar. That night, his hosts removed the valuables from his case and replaced them with dirt. Naḥum Ish Gam Zo continued on his way and was shown before the Caesar who was insulted by the gift and ordered that Naḥum Ish Gam Zo be killed. Naḥum Ish Gam Zo’s reaction was simple: “this too is for the best.”
According to the Gemara, Eliyahu appeared amongst the crowd and suggested that perhaps this is miraculous dirt that the Jews were rumored to have since the days when Avraham fought his enemies with dirt that turned to spears and straw that turned to arrows. They checked it and found that it was true; later they conquered a city with it that they had never been able to conquer before. In appreciation the Caesar sent Naḥum Ish Gam Zo to collect whatever he wanted from the treasury.
On his way home, Naḥum Ish Gam Zo again stopped in the inn where he told the people that the dirt that he had brought had granted him this reward. Hearing this they brought more dirt to the Caesar, but they were killed for their efforts.
In his Sefer HaḤayyim, Rabbi Ḥayyim ben Betzalel (the Maharal’s brother) offers the following explanation. Naḥum Ish Gam Zo recognized that his present had been changed, but felt that what was important was not the value of the present, but the idea that a present was offered, so he continued with his mission. Upon arriving before the Caesar he explained that the dirt symbolized that the Jews were surrendering before him and that it was the patriarch Avraham’s dirt, meaning that Avraham successfully fought wars, but he knew when the best policy was not to fight but to humbly negotiate. Taken with this radical concept, the Caesar tried negotiations with the city that he could not capture, and found that he was successful in his efforts.