Bukhari

(1) Performing the Zuhr prayer in Mina on the Day of Tarwiyah is a Sunnah, but it is not an obligation of Hajj such that any expiation (kaffarah) would become necessary if it is omitted. The Sunnah is that from the Zuhr prayer of the Day of Tarwiyah until the morning of the Day of Arafah, five prayers should be performed in Mina. However, if someone goes directly to Arafat (on the 9th of Dhul-Hijjah) without staying in Mina, there is no harm.

(2) Upon returning from Mina, it is recommended (mustahabb) to perform the Zuhr, Asr, Maghrib, and Isha prayers in Abtah (an open field near Makkah Mukarramah) and to spend part of the night there. This act is called "Tahseeb." After the Messenger of Allah (sallallahu alayhi wa sallam), the caliphs also camped here, and as for those noble Companions (radi Allahu anhum) from whom its negation is reported, this does not negate its being Sunnah or recommended, but rather negates its obligation or compulsion. It does not mean that omitting it affects the Hajj. For details, see: (Fath al-Bari: 3/591)

Explanation:
What is Raf‘ Sababah?
The finger next to the thumb (forefinger/index finger) is called «مُسَبِّحة» (the finger used for tasbih) in Arabic, and in Urdu it is called "Angusht-e-Shahadat" (the finger of testimony), because it is commonly used when glorifying Allah (tasbih) and bearing witness to His oneness. Glorifying Allah and bearing witness to His oneness is the practice of righteous people. Allah Ta‘ala has also granted this finger to immoral people, but instead of using it for tasbih and testimony, they use it for unjust cursing and abuse; therefore, in Arabic it is also called «سَبَّابَة» (the finger used for cursing).

«رَفْع» is also an Arabic word. It is a verbal noun (masdar) and its meaning is "to raise" or "to elevate."

Thus, the meaning of «رَفْع سَبَّابَة» is "to raise the finger of testimony." This is the linguistic explanation.

And technically, in the context of prayer (salah), pointing with the finger of testimony during the tashahhud is called «رَفْع سَبَّابَة».

As with many other issues of prayer, there are different views among various schools of thought regarding this matter. However, according to the Ahl al-Hadith, raising the sababah (index finger) is recommended (mustahabb) and a Sunnah.

The Position of the Hands in the Final Tashahhud

* After sitting for tashahhud following the second prostration in the second rak‘ah, you (the Prophet sallallahu alayhi wa sallam) would place your right hand on your right knee and your left hand on your left knee.

Proof: «إذا قعد فى الصلاة …وضع يده اليسريٰ على ركبته اليسريٰ ووضع يده اليمني على فخذه اليمني .» [صحيح مسلم: 579]

* You would form the number fifty-three (i.e., a circle) with the fingers of your right hand and point with the index finger (i.e., supplicating while pointing).

Proof: «وعقد ثلاثة وخمسين وأشار بالسبابة» [صحيح مسلم: 580]

It is also established that you would place both hands on both thighs, join the thumb with the middle finger (i.e., form a circle), and point with the index finger.

Proof: «وأشار بإصبعه السبابة ووضع إبهامه على أصبعه الوسطي .» [صحيح مسلم: 579]

Therefore, both ways of practice are permissible.

* You would place your right elbow on your right thigh.

Proof: «وحد مرفقه الأيمن على فخذه اليمني .» [ابوداود: 726]

* You would place both forearms on your thighs.

Proof: «وضع ذراعيه على فخذيه .» [نسائي: 1265]

* When you sat for tashahhud, you would point with the index finger.

Proof: «كان إذا قعد فى التشهد … وأشار بالسبابة» [صحيح مسلم: 580]

* You would raise your finger and supplicate with it during tashahhud.

Proof: «قد حلق الابهام والوسطي، ورفع التى تليهما يدعو بها فى التشهد .» [ابن ماجه: 912]

* You would slightly bend the index finger.

Proof: «عن نمير الخزاعي قال: رأيت النبى واضعاً ذراعه اليمني على فخذه اليمني رافعا اصبعه السبابة قد حناها شيئا .» [ابوداود: 991]

“Numeir Khuza‘i says: I saw the Prophet sallallahu alayhi wa sallam (in tashahhud) with his right arm placed on his right thigh, and the index finger of that hand slightly bent and raised.”

* You would continue moving your index finger.

Proof: «ثم رفعه اصبعه فرأيته يحركها يدعو بها .» [نسائي: 1269]

* You would direct your index finger towards the qiblah and continue to look at it.

Proof: «وأشار بأصبعه التى تلي الإبهام فى القبلة ور مي ببصره إليها أونحوها ثم قال: هكذا رأيت رسول الله صلى الله عليه وسلم .» [نسائي: 1161]

* You would make this gesture in both the tashahhud after two rak‘ahs (i.e., the first) and the tashahhud after four rak‘ahs (i.e., the final).

Proof: «كان رسول الله صلى الله عليه وسلم إذا جلس فى الثنتين أو فى الأربع يضع يديه على ركبتيه ثم أشار بأصبعه .» [نسائي: 1162]

Raising the finger at “la ilaha” and lowering it at “illallah” is not established by any authentic hadith. Rather, from the generality of the ahadith, it is established that from the beginning to the end, the circle should be formed and the index finger should be raised. As is mentioned in the narration of Tirmidhi and Nasa’i, that the Messenger of Allah sallallahu alayhi wa sallam saw a man pointing with two fingers (in tashahhud), so he said: «أحّد أحّد» — that is, point with only one finger. From this, it is also established that from the beginning of tashahhud to the end, the index finger should remain raised.

1912. Commentary: The purpose of the statement of Anas radi Allahu anhu is that these matters are not among the obligatory acts. There is no doubt regarding them being the regular practice and Sunnah of the Messenger of Allah sallallahu alayhi wa sallam. However, if due to some excuse one is unable to act upon them, then there is no harm. In matters that are permissible (mubah), one should follow those in authority (ulul-amr) and avoid opposing them.

641 Lexical Explanation:
«رقد رقدة» means "became a little" or "a small amount."
«بالمحصب» refers to the place where the Prophet (sallallahu alayhi wa sallam) performed prayers and also rested, and this was the last day of the journey, i.e., the third day of the Days of Tashreeq.
«محصب» is on the pattern of «محمد». It is the name of a place that is spread between two mountains. Compared to Makkah, it is closer to Mina. It is also called Abtah and Khayf Bani Kinana.
«فطاف به» refers to the Farewell Circumambulation (Tawaf al-Wada‘), and this is the final circumambulation of Hajj.