What is the ruling on the aqiqah on the twenty-first day, and what is the authenticity of the hadith: "The aqiqah is slaughtered on the seventh, or on the fourteenth, or on the twenty-first"?

Firstly: It is appropriate to use "awrada" (ورد) or "dhakara" (ذكر) when referring to hadiths cited by Sheikh Al-Albani, and "akhraja" (أخرج) or "rawaa" (روى) for those who narrated theith with their chain of transmission (isnad).

Secondly: The hadith "The 'Aqiqah is slaughtered on the seventh, fourteenth, or twenty-first day" is weak, and so is the hadith of Umm Kurz which mentions this, especially since Al-Albani deemed it weak.

Thirdly: The recommended time for slaughtering the 'Aqiqah is on the seventh day. However, jurists differed on its permissibility thereafter. The preponderant opinion is that it is permissible on any day after the seventh, and it is even permissible before it, as favored by Ibn Al-Qayyim and the Permanent Committee (Al-Lajnah Ad-Da'imah). Thus, specifying the seventh day is only for recommendation.