` Abdu ` l-Bah Ã was a Persian man who was born on May 23 , 1844 and died on November 28 , 1921 . His father was BahÃ ` u 'll Ã h who founded the religion known as the BahÃ ' Ã Faith . â Abduâ l-Bah Ã ( ' ) ( 23 May 1844 - 28 November 1921 ) , born â AbbÃ s EffendÃ , was the eldest son of BahÃ ` u 'll Ã h , the founder of the BahÃ ' Ã Faith .