What is the ruling on raising the index finger for supplication between the two prostrations, as mentioned in "Zad al-Ma'ad"?

Ibn al-Qayyim's words in "Zad al-Ma'ad" regarding how the Prophet, peace and blessings be upon him, sat between the two prostrations, and how he raised his head from prostration, and placed his hands on his thighs. He mentions his supplication: "My Lord, forgive me, have mercy on me, mend my affairs, guide me, and provide for me." He states that the Prophet's guidance was to prolong this pillar. As for pointing with the finger and moving it, Ibn al-Qayyim did not mention it in the sitting between the two prostrations; rather, it is for the sitting of the tashahhud. He mentioned it in "As-Salat wa Hukm Tarikiha" and in "Zad al-Ma'ad" in another place specifically concerning the tashahhud.