The First Presidency Message in the June 1975 Ensign was entitled, "The Example of Abraham," by President Spencer W. Kimball. An excerpt from his message is as follows:
Abraham’s desire to do God’s will in all things led him to preside over his family in righteousness. Despite all his other responsibilities, he knew that if he failed to teach and exemplify the gospel to his children he would have failed to fulfill the most important stewardship he had received. Abraham’s instruction and example in his home led the Lord to say of him: “For I know him, that he will command his children and his household after him, and they shall keep the way of the Lord, to do justice and judgment.” (Gen. 18:19.)
This excerpt provides some insight as to why Abraham was not considered just a righteous prophet, but why he was also known as the "father of the faithful" (Gal. 3:7; D&C 138:41), and why the 'covenant' was made with Abraham and is renewed through his righteous posterity. Read the rest of this great article online here.