 Shoghi Effendi , the appointed head of the religion from 1921 to 1957 , wrote the following summary of what he considered to be the distinguishing principles of Bahá 'u'lláh 's teachings , which , he said , together with the laws and ordinances of the Kitáb @-@ i @-@ Aqdas constitute the bedrock of the Bahá 'í Faith : 
