ajisari

An ajisari is one who arouses others to pray and feast during Ramadan. He goes from house to house, as early at 2:00 AM, beating his kettle drum with a stick and singing (screaming) at the top of his voice. This is purely a religious duty; it is voluntary. Although the ajisari does not expect to be compensated by his fellow believers, he believes that Allah will reward him, in the hereafter, for forsaking his bed and discomforting himself during the month-long fasting period.
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