188 In liN F~fllt/JJ of fbi ProphttChristians in the norm. The Muslims wefe not to find this OUI until a few
weeks later; for the moment, the news from the north was rather alarm-
ing. E"erything suggested that Heraclius's By'/.antine armies had allied
with the Arab tribes and that together the~' were preparing a full-scale
attack against 1£uhammad, "the new Emperor of the Arabs," An imme-
diate reaction was rC<Jwred, and the stakes were so important and the
expedition so dangerous that for the first time the Prophet informed all
his Companions of his d estination. They were to march to the north prc-
veno,·cly. in order to anticipate the advance of enemy trOOpS and if nec-
essary surprise mem on their own territory. The season was not fa\'orable
and the army was going to face intense heat until they reached the north.
Mobilization was general, and the Prophet asked the Companions to con-
tribute as much as they could to defray the cost of the expedition. Umar
gave half his fonune and understood as a !esson in se lf-abnegation the
behavior of Abu Bakr, who put everything he had at th e Prophet'S dispos-
al. Uthman similarly stood out by supplying mounts for half the army. All
the camels and horses in the afea were requisitioned, but they did not suf-
fice to provide for the needs of all the soldiers; as a result, the Prophet
had to refuse some Companions' requests [Q participate in the expedition,
and some of them wcpt, so crucial did they know the expedition to be.
The expected mjght of the enemy was such that the community'S future
was clearly at stake. The army set out at the end of the year 630 (the ninth
year of bijrah); there were thirty thousand men, and the Prophet was in
command. He asked Ali to stay behind with his family. Ali was mocked by
the hypocrites: he could not hear it and eventually caught up with the
army at their first camp. However, the Prophet sent rum back and asked
him to be as Aaron had been for his brother lo.' 10 5es, the guard ian o f his
people while he was away.
The heat was intense, as expected, and the march to the north was dif-
ficult. Four of the Prophet'S faithful Companions had preferred to stay in
Medina, aware that the journey would be difficult. One of them, Abu
Khaythamah, felt dcep remorse and after about ten days decided to catch
up with the expedition. He arrived when they had already encamped at
Tabuk. The Prophet was particularly happy to see him arrive, so saddened
had he been by the four Companions' defection, which could only be
inte rpreted as cowardice o r treason. Abu Kha),thamah was forgiven when
he explained his remorse and the imperacive need he had felt to catch up