Under what circumstances may a ruler selectively accept one banquet over another?

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The ruler may accept one invitation while declining another if a specific, valid excuse prevents him from attending the first but not the second. Examples of such distinguishing excuses include the presence of an apparent evil (munkar) at one banquet, the location of one being too distant, or the commitment to one requiring a significant duration, while the other lacks such constraints. In such cases, acceptance of the latter is permissible because the excuse for avoiding the former is evident.