I say, and with God's success: Ablution has obligatory acts, Sunnah, and recommended acts, but there are no mandatory acts; to avoid equating the followers - the followers of prayer and the followers of ablution, while there is a distinction between the original acts of prayer and ablution - because ablution is of a lower rank than prayer; it is obligatory for something else, as it is a condition, and conditions are followers, while prayer is obligatory in itself. If we were to say that there is a mandatory aspect in completing ablution, as we say there is in completing prayer, it would lead to the aforementioned equality, so we said: it is Sunnah in completing ablution; to demonstrate the difference between them. This is likened to the fact that the minister's servant must be of a lower status than the prince's servant, because the minister is of a lower rank than the prince. It is more appropriate to say that the lack of obligation in ablution is due to the absence of what establishes it, which is the existence of a definitive proof that is ambiguous in its indication, or an ambiguous proof that is definitive in its indication. Refer to: Al-Tawdeeh, the explanation of the introduction of Abu Al-Layth, and God knows best.