Muhammad: Victory and DeathThe alms tax ("zakat") is said to have been made obligatory (cf. Qur'an
9:11), and Muhammad reportedly sent out his representatives to collect it
from the various tribes (cf. Qur'an 9:60).^245
The intercalary month of the pagan Arabs, which adjusted the lunar
calendar to compensate for the seasons (and thus postponed the "holy
months"), was abolished (cf. Qur'an 9:36f). With respect to the Gregorian
calendar, the months of the Islamic calendar begin about 10-12 days earlier
in each successive year.
During the 109th month after the Hijra, Muhammad sent Khalid b. Walid to
raid the Banu `Abdulmadan at Najran.^246
In the 110th month after the Hijra, Khalid was said to have be^247 en sent to
the Banu al-Harith b. Ka`b at Najran. After inviting them to Islam, they are
reported to have accepted. Khalid is said to have taught them Islam and the
book of Allah, and later accompanied their deputation to Muhammad.^248
According to one tradition, Khalid was in Yemen for six months, and then
`Ali arrived to relieve him.^249
During the 115th month after the Hijra, Muhammad sent Ali b. Abu Talib and 300 men to Yemen with orders to be mild on them, in order to win them over to Islam. The Muslims raided the Banu Madhhij and captured women and children and seized livestock. After a force of the Banu Madhhij had mobilized,Ali invited them to Islam, but they refused. The
Muslims attacked, killing 20 men, and their enemy fled. Instead of pursuing
them, however, `Ali invited them to Islam again. This time the Banu
Madhhij accepted and agreed to pay the alms tax.^250
Especially after the Hajj of 9 AH and the sending out of the tax collectors,
many of the Arab tribes are said to have sent deputations to Muhammad.^251
During this time period, the three "false" prophets, Musaylima in al-
Yamama, al-Aswad in Yemen and Tulayha in the country of the^252253
Asad are said to have risen up against Muhammad. Of these,^254255