Question 33: Why is Takbeer at the beginning of the Salat?
Imam Ahmed AlHasan a.s. answers in The Allegories: In your Salat you want to ascend to Allah and face the Exalted and Mighty,so Salat is the ascension of the believer and the ascension will not happen only until you ascend up the seven skies, and the key to every sky and the ascension to and from it until you go to the next one is “Allahu akbar.”
Meaning the lacking poor servant intends to go to the Complete and Wealthy, and I want to ascend to reach Him the Exalted, to face Him and praise Him and revere Him and glorify Him the Exalted for His bounties and blessings upon me.