Late in the six year A.H., on his return from Hudaibiyah, the Prophet (Peace be upon him) decided to send messages to the kings beyond Arabia calling them to Islam. In order to authenticate the credentials of his envoys, a silver seal was made in which were graven the words: “Muhammad the Messenger of Allâh” in the following formation:
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ÑÓÜÜæá
Çááå
Envoys were chosen on the basis of their experience and knowledge, and sent on their errands in Muharram in the year 7 A.H., a few days before heading for Khaibar.
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