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There was no time to waste, so Salman instructed the Companions on the
depth and width of the trench, and the digging began. Because Salman had
until recently been the slave of the tribe of Krayzah he knew his former
masters owned many tools. Because of this it was agreed that they should
be asked to loan them in accordance with the pact they had signed with the
Prophet (salla Allahu alihi wa salaam) a few years ago that also stated they
would not ally themselves with the enemy of the Prophet (salla Allahu alihi
wa salaam).

The Krayzah were quick to realize that they stood to lose their possessions
and date groves if they did not help defend Medina and so every tool they
possessed was made available and work began.

Each section of the Muslim community was assigned a specific area to
excavate and soon the continuous sound of axes hacking away at the
ground and shovels removing the loosened ground filled the air, coming only
to a halt at the time of prayer and when sleep finally overtook them.

Prophet Muhammad (salla Allahu alihi wa salaam) worked tirelessly