Al-Albaani: I want to remind my brothers who are here that I noticed when some of them are praying and they move their finger in tashahhud, they move it too much in a way that is not legislated.

There is no doubt that moving the finger in tashahhud is the Sunnah, but many times our brothers from Ahlus-Sunnah mix this movement [of the finger] up with another thing which is not from the Sunnah, and that is lowering and raising it.

I noticed in this mosque that the brother, the Imaam, may Allaah reward with him good, is active in spreading the Sunnah, for I saw some of the people in the mosque moving their fingers in tashahhud, and this is proof that the Imaam, walhamdulillaah, is carrying out the duty of calling to the Sunnah.

So I saw some of these people and [also] some of our brothers with us on this trip, [I noticed] that they add something to this movement which can be described as lowering and raising, i.e., this is lowering and raising—this has no basis in the Sunnah, all that has been mentioned in the Sunnah is that it is moved, i.e., there is a Sunnah that should be observed when moving [the finger], i.e., that the finger should be pointing towards the Qiblah, so when you point it towards the Qiblah and move it, don’t lower it, because if you do then you have made it point towards the ground, and the ground is not your Qiblah, the Qiblah is in front of you.

So here is your knee, and your palm is on your knee, so as soon as you sit you curl your fingers up and make a circle with your thumb and your middle finger, then you raise your index finger and move it—don’t raise and lower it—this has no basis in the Sunnah, rather you move it in its place.

This is what I wanted to remind you of and reminders benefit the believers.

Al-Hudaa wan-Noor, 494.

Also refer to this post for further clarification.