How do we know Jesus is the rightful heir?

In the context of Genesis 25, Isaac is presented as the rightful heir because he is the son of Abraham and Sarah, established by God's promise. Parallel to this, Jesus is identified as the rightful heir in God's redemptive plan, being the only begotten Son of God. Hebrews 1:2 states, 'Hath in these last days spoken unto us by his Son, whom he hath appointed heir of all things, by whom also he made the worlds.' This establishes Jesus’ unique position as the heir, fulfilling the prophecy originating from the promise made to Abraham.