Abraham left Ur by faith, and it was also by faith that Abraham left Haran. He sojourned in the Promised Land by faith as well.
We are told that despite becoming quite wealthy, and with the exception of a burial place for Sarah and himself, never owning a piece of land, he lived the entire time in tents and that the Canaanites lived in the land with him (Genesis 13:2; 23:1-20). This establishes another general pattern for his faithful children. In every sense of the word, he was a pilgrim. No matter where he lived or what were his economic circumstances, he purchased no land—he never even built a house!
Beyond this, the Bible reveals little social interaction with others outside of his family. Except for a league made with his nearest neighbors, Abraham made no alliances, nor took any part in the politics or the religions of the people of the land. He lived this way for one hundred years. Isaac and Jacob shared the same pattern of life.
God shows us all of this so we might see that virtually Abraham's entire post-calling life was engaged in living by faith, focused on maintaining his relationship with God. He truly was in the world but not of it. He did not cultivate its friendship but used it as necessity required, though in a guarded way, lest he should in some way abuse his privileges with God.