The ruling on moving the finger during the tashahhud and movement in prayer

Question:
Among the questions of this questioner, he says: O His Eminence the Shaykh: Is it permissible to move the finger during the tashahhud, or not? Especially during the first tashahhud. And the Messenger of Allah (peace and blessings be upon him) said: "Three movements invalidate the prayer." Is this a hadith?

Answer:
It is not a hadith: "Three movements invalidate the prayer" is not a hadith, but rather it is the statement of some scholars.
And the Sunnah is to point with the index finger during the tashahhud. From the time one sits for the tashahhud, he points with the index finger to the oneness of Allah, to the fact that Allah is One. He moves it during the supplication, and he moves it slightly during the supplication, at: "O Allah, send blessings upon Muhammad," and during the supplication he moves it slightly. He keeps it upright from the time he sits for the tashahhud until he says the taslim, as a sign of tawhid.