Raising the hands during the Iftitah Takbir (the opening takbir) is considered a sunnah in Islamic prayer. This practice is based on the example of the Prophet Muhammad (PBUH), who raised His hands when performing this takbir (Bukhari, Azan, 84 [736]; Muslim, Salat, 21-22 [390]; Tahaawi, Sharh Ma’ani’l Asar, 1/195-196 [1157-1170]).
In the Hanafi school of thought, men raise both hands with their palms facing the Qibla, and the thumbs align with the earlobes. Women, on the other hand, raise their hands up to the level of their shoulders. In other schools of thought, men raise their hands to shoulder height as well.