This is the view adopted by the author, and it is the position of the madhhab: the fifty oaths are apportioned among the male heirs, and if there is only one, he swears all fifty.
The second view on the issue is that there must be fifty men, each swearing one oath, based on the Prophet’s ﷺ words: “Fifty men among you are to swear.” He did not say, “You are to swear fifty oaths.” This is also more cautious and more effective, because when this group or tribe knows that fifty of them must swear, some may advise the others, saying, for example, “Fear Allah and do not make us bear sin.” Thus, there is benefit and advantage in it.
This view is closer to the apparent meaning of the evidence: fifty men must take the oath.
But how are these men to be selected? We say: the nearest relatives are considered first, then those who would inherit after them, then those who would inherit after the latter—giving priority to the closest in succession.
For example, if there are sons, a father, brothers, nephews, and paternal uncles, and the fifty oaths are completed with the nephews, then the paternal uncles are not required to swear.
His statement, “If the heirs decline to swear, or if they are women, the defendant swears fifty oaths and is exonerated”: that is, the heirs say, “We will not swear concerning something we did not witness.” The oath is then referred to the defendant, as stated in the hadith, and he is told, “Swear fifty oaths.”