At the beginning of Genesis 28, Isaac finally blesses Jacob without having to be tricked, but still after being prodded by his dutiful wife.
And Isaac called Jacob, and blessed him, and charged him, and said unto him, Thou shalt not take a wife of the daughters of Canaan. Arise, go to Padanaram, to the house of Bethuel thy mother’s father; and take thee a wife from thence of the daughers of Laban thy mother’s brother. And God Almighty bless thee, and make thee fruitful, and multiply thee, that thou mayest be a multitude of people; And give thee the blessing of Abraham, to thee, and to thy seed with thee; that thou mayest inherit the land wherein thou art a stranger, which God gave unto Abraham.” (Gen. 28:1-4)
We have a reiteration of the promise coupled with the same “foreigner” or “stranger” language. The patriarchs must first be pilgrims in the promised land before they can inherit it, and this is our context for the New Testament use of similar language regarding the Christian’s current state.