When you inherit something it is passed down from an ancestor and you have legal right to possess it. Terah took his family from Ur "to enter the land of Canaan" (Ge 11:31). After he died "the Lord said to Abram, 'Go forth from your country . . . to the land which I will show you'" (12:1). He also said, "'I will make you a great nation'" (:2). "By faith Abraham, when he was called, obeyed by going out to a place which he was to receive for an inheritance" (Heb 11:8). Then he was told, "'Your reward will be very great'" (Ge 15:1). But he didn't see how it was possible because his only heir was his head servant (:2). God replied, "'One who shall come forth from your own body, he shall be your heir'" (:4). Then God directed him, "'Count the stars, if you are able to count them . . . so shall your descendants be'" (5). Consequently Abram "believed in the Lord; and He reckoned it to him as righteousness" (:6). "God has granted [the inheritance] to Abraham by means of a promise" (Gal 3:18). God said "'I have made you the father of a multitude of nations'" (Ge 17:5) which took the form of a covenant. God said, "'This is My covenant, which you shall keep, between Me and you and your descendants after you: every male shall be circumcised'" (:10). It was a "sign of the covenant" (:11), and without it, a person "'has broken My covenant'" (:14). God then said, "'I will give you and your descendants after you, the land of your sojournings, all the land of Canaan, for an everlasting possession; and I will be their God'" (:8).
In order to accomplish this it would have to be a miracle, but that would prove that only God could do it. When the "Lord appeared to Abram" (Ge 17:1) he said, "'Indeed I will give you a son by her . . . and she shall be a mother of nations'" (:16). "By faith even Sarah herself received ability to conceive . . . since she considered Him faithful who had promised" (Heb 11:11). God told Abram, "'You shall call his name Isaac; and I will establish My covenant with him for an everlasting covenant for his descendants after him'" (Ge 17:19). Furthermore, God said, "'I have chosen him . . . in order that the Lord may bring upon Abraham what He has spoken about him'" (18:19). They sang, "'Thou wilt bring them and plant them in the mountain of Thine inheritance, . . . Thy dwelling'" (Ex 15:17). This was Mount Zion in the Promised Land where the temple was later built. Joshua was told by Moses, "'Go with this people into the land which the Lord has sworn to their fathers to give them, and you shall give it to them as an inheritance'" (Dt 31:7).