And I will bless them that bless thee, and curse him that curseth thee: and in thee shall all families of the earth be blessed. Genesis 12:3
At first glance this only appears to be a prophecy about Israel. However as you see at the end of the scripture, it says “All The Earth Will Be Blessed”. How and Why are the questions? Well it started with Abraham and ended with Jesus Christ!
Little did Abraham know or understand , that his promised seed of Isaac would eventually lead to the Messiah. As God told Abraham “You would have descendants as numerous as the stars and sand on the shore” (Genesis 26:4, Genesis 22:17)
And the scripture, foreseeing that God would justify the heathen through faith, preached before the gospel unto Abraham, saying, In thee shall all nations be blessed. So then they which be of faith are blessed with faithful Abraham. Galatians 3:8-9
The Apostle Paul clarifies this, that we are all justified by faith in God just as Abraham was. Its by faith in Christ you are saved, not by your works. Same with Abraham it was his faith in God that saved him and not his works.
Second we through Jesus Christ are spiritual descendants of Abraham. The entire world will be blessed through Jesus Christ! The Messianic Seed that was promised since the beginning in Genesis. The word Heathen here is used interchangeably with Gentile
Understand that the Bible is a continuous book in complete harmony with each other. God had a redemption plan for humanity and it was through Jesus Christ! Amen