The Prophet ﷺ said: “Deeds are according to intentions and every person will be rewarded according to his intention. Therefore, whosoever has emigrated for the sake of Allah and His Messenger, then his emigration was for Allah and His Messenger. And whosoever emigrated for the sake of a worldly gain, or a woman “whom he desires” to marry, then his emigration is for the sake of that which “moved him” to emigrate.” [ Source: Bukhari.]
From the Prophet’s statement ﷺ “Perform Sa’y (between them) for indeed Allah has decreed that you perform Sa’y (between them).” [ Source: Ahmad.]
because the Prophet ﷺ said: “Hajj is ‘Arafah.”
Allah said: “…and circumambulate the Ancient House.” (al-Hajj: 29)
Concerning omitting one of The Pillars of Hajj; if it is Ihram, then his religious rites are not established since he has not made his niyya (intention), and there is no act of worship without the correct niyya. If, however, it is another pillar, then he has not completed his religious rites until he fulfils it.
the Prophet ﷺ after listing the mawaqeet said: “Those mawaqeet are for their residents and non residents who pass through them with the intention of making Hajj or ‘Umrah.” [ Source: Bukhari.]
because the Prophet ﷺ stayed there until sunset.
because the Prophet ﷺ spent the night there. He said: “My nation should take its religious rites (from me), because I do not know if I shall be with them after this year.” [ Source: Ibn Majah.] He ﷺ permitted the weak Muslims (to leave for Mina) only after the middle of the night. This indicates that spending the night in Muzdalifah is obligatory, and Allah ordered the pilgrims to engage in His remembrance at Al-Mash’ar Al-Haram (Muzdalifah).
as it is established that the Prophet ﷺ permitted the camel herders to not spend the night at Mina. [ Source: Abu Ya’la in his Musnad.] This shows that the original ruling is that spending the night in Mina is obligatory.
Allah says: “And remember Allah during (specific) numbered days.” (al-Baqara: 203). The specific numbered days: The days of at-Tashreeq.
Stoning the pillars is a form of remembrance of Allah, the Most High, due to the Prophet’s statement ﷺ: “Indeed circumambulating the House, (the circuits) between as-Safa and al-Marwa, and stoning the pillars; all have been ordained to serve as a (form of) remembrance of Allah.” [ Source: Abu Dawud.]
Allah says; “Certainly, you shall enter al-Masjid al-Haram, if Allah wills, secure, (some) having their heads shaved, and (some) having their hairs cut short.” (al-Fath: 27)
as confirmed on the authority of Ibn Abbas t: “The people were ordered to make the last of their worship (to be) at the House, but this has been waived for the menstruating women.” [ Source: Muslim.]
1- Bathing and perfuming before assuming Ihram.
2- Wearing a wrapper (garment) and cover cloth which are white.
3- Saying the Talbiyah, starting when assuming Ihram and continuing until stoning Jamaratul aqabah.
4- The arrival circumambulation for those performing Ifrad or Hajj al-Qiraan.
5- Raml in the first three rounds during the arrival circumambulation.
6- Observing al-Idh’tiba’ during the circumambulation of arrival, and this is done by passing the cover cloth under the right armpit and placing the ends of the cloth on one’s left shoulder.
7- Spending the eve of Arafah at Mina.
8- Kissing the Black Stone.
9- Praying Maghrib and Isha’ prayers merged and advanced at Muzdalifah.
10- Staying at Al-Mash’ar Al-Haram (the revered landmark) in Muzdalifa from Fajr until sunrise, if possible, otherwise it is acceptable to stay at any place in Muzdalifah.
Whoever omits a supererogatory act (sunnah) of Hajj has not committed any violation and his Hajj is still valid.
Whoever omits an obligation must offer blood (sacrifice an animal) to make up for this omission.