11 – It is obligatory to face the qiblah for the prayer, and this is a condition for its validity.

12 – The pillars must be observed in the prescribed order, because the ḥadith employs the word thumma (then), and the context is one of instructing someone ignorant of the rulings.

13 – These pillars are not waived on account of ignorance or forgetfulness. This is shown by the Prophet’s command that the man repeat the prayer; he did not suffice with merely teaching him, because these are mandatory acts whose omission is not excused by ignorance or lapse of memory.

14 – The prayer performed by the ill-performing worshipper in the manner he offered it is invalid and does not fulfil the obligation; otherwise he would not have been told to repeat it. Let this be a lesson and an admonition for those who peck at their prayers without completing them, and let them realise that such a prayer is not acceptable.
Shaykh al-Islām said: His statement “fa-innaka lam tuṣalli” (for you have not prayed) negates the act’s being a prayer. An act is only negated when something obligatory is missing; it cannot be negated merely because a recommended element was omitted.
Al-Ṣanʿānī said: It is untenable to interpret the negation as a negation of perfection, for words of negation are originally coined to negate the very reality of a thing.

15 – Whoever, out of ignorance, performs an act of worship incorrectly and its appointed time has elapsed is not required to make it up. This rests on the legal maxim cited by Shaykh al-Islām Ibn Taymiyyah: “Commands of the Law do not bind the legally responsible person until he has knowledge of them; likewise, one who omitted an obligation before the ruling reached him—such as a person who did not perform tayammum in the absence of water because he thought it invalid, or one who did not cease eating until the white thread became distinct from the black thread—is not held accountable for what preceded his knowledge.”

16 – Sound instruction and the manner of enjoining right are legislated: they should be delivered gently and with ease, so as not to repel the learner, for he may reject what he is taught if it comes with harshness and severity.

17 – It is recommended for the one answering a question to add further clarification whenever benefit requires it—for example, when the circumstances indicate that the questioner is unaware of certain rulings he needs to know.