What is the legal implication of specifying 'with its two prostrations' (bisajdatayha)?

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The phrase 'with its two prostrations' may be included for emphasis, similar to the usage in Quran 6:38, 'And no bird that flies with its wings' (Wala tairun yattiru bijanāhayhi). Alternatively, it serves to exclude one who managed to join the Imam for the prayer but missed both prostrations, or one prostration, due to crowding, forgetfulness, sleep, or inattention before the Imam concluded the prayer with the Taslim (salutation).