Is it permissible to raise the finger after ablution and say "Lā ʾilāāh illā Allāh" (There is no god but Allah)?

The Prophetic Sunnah does not mention the desirability of raising the index finger for the Tashahhud after ablution (Wudu'). The fundamental principle in acts of worship is Tawqif (restriction to what is prescribed). What is legislated for a Muslim after Wudu' is to say: "I bear witness that there is no god but Allah alone, without any partner, and I bear witness that Muhammad is His servant and His messenger. O Allah, make me among those who repent and make me among those who purify themselves." Raising the index finger is confirmed during the Tashahhud in prayer and when the Khateeb (preacher) supplicates, but not after Wudu'. It is also inappropriate to describe scholarly ijtihad (independent reasoning) as a "final word" unless it is supported by definitive evidence.