The image below is
a screen shot displaying Reliance of the Traveller,
Book O, Ch.9.1 ,
as it appeared in my browser, which was pointed to the search
result
from http://www.muhaddith.org/cgi-bin/e_optns.exe
. I had searched for each year because that phrase is used in
the description of the obligation to attack Kuffar who are passively
minding their own affairs at home. This is a link to the ayat
cited in the text: 4:95.
See http://en.wikipedia.org/wiki/Fard
for the details of the concept of obligation as communal and
individual. When Islam is the aggressor, the obligation is
fard al-kifaya, individuals are excused once a sufficient
number have reported to the battle front. When kuffar invade
Muslim lands, the obligation is fard al-ayn, binding on all who are
able to fight.
Pay particular attention to the the text
following the citation to 4:95. It informs us that there is an annually
recurring obligation to attack kuffar. Al Shafi'i has made
the matter perfectly clear.
"The
least that the imam must do is that he allow no year to pass without
having organised a military expedition by himself, or by his raiding
parties, according to the Muslims' interest, so that the jihad will
only be stopped in a year for a (reasonable) excuse."