1؎ : As the author himself has explained, this is regarding making a gesture with the index finger during the tashahhud (both the first and second sitting). From the very beginning of the tashahhud, a circle is to be formed with the thumb and middle finger, and the index finger is to be repeatedly raised, continuously bearing witness to the oneness of Allah, not only at «أشہد أن لا إلہ إلا اللہ» as has become customary in the Indian subcontinent. The hadith explicitly states that the Messenger of Allah (sallallahu alayhi wa sallam) would form a circle with his fingers and gesture with the index finger, or keep moving it. There is no restriction regarding the specific place for this action.
Explanation & Benefits
Shaykh Dr. Abdur Rahman Freywai
Explanation: 1: As the author himself has explained, this is regarding making a gesture with the index finger during the tashahhud (the first and second sitting in prayer). From the very beginning of the tashahhud, one should form a circle with the thumb and middle finger, and continuously bear witness to the oneness of Allah by repeatedly raising the index finger, not only at (ashhadu alla ilaha illallah) as has become customary in the Indian subcontinent. It is explicitly stated in the hadith that the Messenger of Allah (sallallahu alayhi wa sallam) would form a circle with his fingers and gesture with the index finger, or keep moving it. There is no restriction regarding the place (in the tashahhud) for this action.
Source: Sunan al-Tirmidhi – Majlis ‘Ilmi Dar al-Da‘wah, New Delhi Edition, Page: 3557
´It was narrated from Abu Hurairah that:` A man used to supplicate with two fingers and the Messenger of Allah (ﷺ) said: "Make it one, make it one."
Hafiz Muhammad Ameen
1273. Commentary: The gesture with two fingers will either be with two fingers of the right hand itself, or it is also possible that it is with the index fingers of both hands. Since this gesture is a practical expression of tawhid (the oneness of Allah), it should therefore be done with only one finger.
Source: Sunan Nasa'i: Translation and Benefits by Shaykh Hafiz Muhammad Amin Hafizullah, Page: 1273