Answer:
Because we pray the way our Blessed Prophet prayed, and that is the way the Prophet Muhammad 
was taught Salat by Sayyidina Gibril.
Also, there are many great open and hidden blessings in the way we pray: standing-bowing-prostrating-sitting etc., the number of rak`ats, the supplications we say, their words and numbers, etc. Among those blessings: healing of the heart, mind, and body; taming the dragons that nest in the breast; purification; concentration; discipline; connection with our Lord and the Highest Assembly, the angels; obedience of our Prophet; oneness with the Believers; rehearsing thanks and adoration of our Lord; placing our hopes and fears in His Hands; obtaining forgiveness; losing oneself in His Highest praise; acknowledging that we are nothing and only He remains; surrendering to His Will…
Hajj Gibril Haddad
