Abraham (originally Abram) is the common patriarch of the Abrahamic religions, including Judaism, Christianity, and Islam. In Judaism, he is the founding father of the covenant of the pieces, the special relationship between the Hebrews and God; in Christianity, he is the spiritual progenitor of all believers, Jewish or Gentile; and in Islam he is seen as a link in the chain of prophets that begins with Adam and culminates in Muhammad. Wikipedia, Abraham

Cayce
"In the application and study, then, of all influences that go to make up the developments, - as the entity may find, as indicated to the entity in that just stated, the unfoldment of the mind as may be paralleled by the history of the communication of spirit, or God, with individual entities from Abraham to Christ, may be seen in thine own children. For, this is the manner to make same practical, - that knowledge ye have gained in not only watching but aiding in the unfoldment of their minds. Do not put off questions asked too long to be answered. And have an answer when the question is asked." [Cayce 281-63]