with    willing submission, and feel    themselves  subdued.’’  The
Prophet  Muhammad    himself     elaborates  these   choices     in  a
well    known   Hadith.[27]
From    the earliest    days    of  Islam,  Muslims have    acted   on
these    commands.   First   Muhammad    unified     the     Arabian
peninsula    under   his     rule    and     directed    that    all     religions   be
forbidden   there   except  Islam.  (This   is  why even    today   Saudi
Arabia  forbids all religions   except  Islam   to  be  practiced   on
its soil.)
Then    the Muslims turned  to  the larger  non-Muslim  world.
Muslim  Arabia  was surrounded  by  predominantly   Christian
lands,  particularly    the Byzantine   imperial    holdings    of  Syria,
Palestine,  and Egypt.  Four    of  Christendom’s    five    principal
cities   —   Constantinople,     Alexandria,     Antioch,    and
Jerusalem    —   lay     within  striking    distance    of  Arabia.     The
Byzantine   Empire’s    great   rival,  Persia, also    had a   significant
Christian   population.
Muhammad     himself     made    the     first   Islamic     overtures   to
these    neighbors.  He  sent    letters     to  the     leaders     of  Persia,
Byzantium,   and     Abyssinia,  exhorting   them    to  ‘‘embrace
Islam   and you will    be  safe.’’ None    did,    and Muhammad’s
warning  proved  accurate:   none    of  them    were    safe.[28]   In
635 (just   three   years   after   the Prophet’s   death), Damascus,
the city    where   Paul    had seen    the great   vision  that    turned  him
from    a   persecutor  of  Christianity    to  its energetic   apostle,    fell
to  the invading    Muslims.    The next    year,   Antioch,    where   the
disciples   of  Jesus   were    first   called  ‘‘Christians’’  (Acts   11:26)
also    fell.   It  was Jerusalem’s turn    two years   later,  in  638.