What is the ruling on looking at the index finger during the Tashahhud until its completion?

The Sunnah (definition) according to the Shafi'is and Hanbalis is to look at the index finger during the tashahhud (definition) until its completion, based on the hadith (definition) narrated by Abdullah ibn Al-Zubayr (may Allah be pleased with both of them): "When the Messenger of Allah (peace be upon him) sat for the tashahhud, he would place his left palm on his left thigh, and he would point with his index finger, his gaze not going beyond his pointing." The Malikis and Hanafis differed on this. The preponderant opinion regarding looking during the tashahhud is that of the Shafi'is and Hanbalis, due to its conformity with the hadith.