Plutarch tells us that Fabius believed that the disaster at Lake Trasimene was due, in part, to the fact that the Gods had become neglected. Before that battle, a series of omens had been witnessed, including a series of lightning bolts, which Fabius had believed were warnings from the Gods. He had warned Flaminius of this, but Flaminius had ignored the warnings. And so Fabius, as Dictator, sought next to please the Gods. He ordered a massive sacrifice of the whole product of the next harvest season throughout Italy, in particular that of cows, goats, swine, and sheep. In addition, he ordered that musical festivities be celebrated, and then told his fellow citizens to each spend a precise sum of 333 sestertia and 333 denarii. Plutarch isn't sure exactly how Fabius came up with this number, although he believes it was to honor of the perfection of the number three, as it is the first of the odd numbers, and one of the first of the prime numbers. It is not known if Fabius truly believed that these actions had won the Gods over to the Roman side, although the actions probably did (as intended) convince the average Roman that the Gods had finally been won over.
Fabius was well aware of the military superiority of the Carthaginians, and so when Hannibal invaded Italy, Fabius refused to meet him in a pitched battle. Instead he kept his troops close to Hannibal, hoping to exhaust him in a long war of attrition. Fabius was able to harass the Carthaginian foraging parties, limiting Hannibal's ability to wreak destruction while conserving his own military force. The delaying tactics involved a pincer of not directly engaging Hannibal while also exercising a "scorched earth" practice to prevent Hannibal's forces from obtaining grain and other resources.
The Romans were unimpressed with this defensive strategy and at first gave Fabius his epithet as an insult. The strategy was in part ruined because of a lack of unity in the command of the Roman army, since Fabius' Master of the Horse, Minucius, was a political enemy of Fabius. At one point, Fabius was called by the priests to assist with certain sacrifices, and as such, Fabius left the command of the army in the hands of Minucius during his absence. Fabius had told Minucius not to attack Hannibal in his absence, but Minucius disobeyed Fabius and attacked anyway. The attack, though of no strategic value, resulted in the retreat of several enemy units, and so the Roman people, desperate for good news, believed Minucius to be a hero. Upon hearing of this, Fabius became enraged, and as Dictator, he could have ordered Minucius' execution for his disobedience. One of the Plebeian Tribunes (chief representatives of the people) for the year, Metilius, was a partisan of Minucius, and as such he sought to use his power to help Minucius. The Tribunes were the only magistrates who were independent of the Dictator, and so with his protection, Minucius was relatively safe. Plutarch states that Metilius "boldly applied himself to the people in the behalf of Minucius", and had Minucius granted powers equivalent to those of Fabius. By this, Plutarch probably means that as Plebeian Tribune, Metilius had the Plebeian Council, the popular assembly which only Tribunes could preside over, grant Minucius quasi-dictatorial powers.
Fabius did not attempt to fight the promotion of the overly-ambitious Minucius, but rather decided to wait until Minucius' rashness caused him to run headlong into some disaster. He realized what would happen when a man so favored by the people served them worse than did the man who had been so ill-treated by them. Fabius, we are told, reminded Minucius that it was Hannibal, and not himself, who was the enemy. Minucius proposed that they share the joint control of the army, with command rotating between the two every other day. Fabius rejected this, and instead let Minucius command half of the army, while he himself commanded the other half. Minucius openly claimed that Fabius was cowardly because he failed to confront the Carthaginian forces. Near the present-day town of Larino in the Molise (then called Larinum), Hannibal had taken up position in a town called Gerione. In the valley between Larino and Gerione, Minucius decided to make a broad frontal attack on Hannibal's troops. Several thousand men were involved on either side. It appeared that the Roman troops were winning but Hannibal had set a trap. Soon the Roman troops were being slaughtered. Upon seeing the ambush of Minucius' army, Fabius cried "O Hercules! how much sooner than I expected, though later than he seemed to desire, hath Minucius destroyed himself!" Upon ordering his army to join the battle and rescue their fellow Romans, Fabius exclaimed "We must make haste to rescue Minucius, who is a valiant man, and a lover of his country."
Fabius rushed to his co-commander's assistance and Hannibal's forces immediately retreated. After the battle there was some feeling that there would be conflict between Minucius and Fabius; however, the younger soldier marched his men to Fabius' encampment and he is reported to have said, "My father gave me life. Today you saved my life. You are my second father. I recognize your superior abilities as a commander." It was only after Fabius had saved him from an attack by Hannibal that Minucius placed himself under Fabius' command. When Fabius' term as Dictator ended, Consular government was restored, and Gnaeus Servilius Geminus and Marcus Atilius Regulus assumed the Consulship for the remainder of the year.
Shortly after Fabius had laid down his Dictatorship, Gaius Terentius Varro, was elected Consul. He rallied the people, through the Roman assemblies, and won their support for his plan to abandon Fabius' strategy, and engage Hannibal directly. The rashness of Varro didn't surprise Fabius, but when Fabius learned of the size of the army (eighty-eight thousand soldiers) that Varro had raised, he became quite concerned. Unlike the losses that had been suffered at the hands of Mincuius, a major loss by Varro had the potential to kill so many soldiers that Rome might have had no further resources with which to continue the war. Fabius had warned the other Consul for the year, Aemilius Paulus, to make sure that Varro remained unable to directly engage Hannibal. According to Plutarch, Paulus replied to Fabius that he feared the votes in Rome more than Hannibal's army.
When word reached Rome of the disastrous Roman defeat under Varro and Paulus at the Battle of Cannae, the Senate and the People of Rome turned to Fabius for guidance. They had believed his strategy to be so flawed before, but now, they thought him to be as wise as the Gods. He walked the streets of Rome, assured as to eventual Roman victory, in an attempt to comfort his fellow Romans. Without his support, the senate might have remained too scared to even meet. He placed guards at the gates of the city to stop the frightened Romans from fleeing, and regulated mourning activities. He set times and places for this mourning, and ordered that each family perform such observances within their own private walls, and that the mourning should be complete within a month, at which point the entire city would be purified (probably via a lustrum).