Chapter on the Manner of Prayer, Explanation of the Fifty-One Rak‘ahs; The Order, Recitation, Tasbih in Bowing and Prostration, Qunut, and What is Obligatory and Recommended Therein

His عليه السلام statement: ‘And if you wish, then after it’ is to be understood as referring to a situation of making up (missed prayer) or due to ‘taqiyyah’ (precautionary dissimulation), according to the school of thought of some among the general populace regarding the Fajr prayer.