Is the Abrahamic covenant to Abraham still in effect today?

The Abrahamic covenant remains valid and true today. God has not changed His mind, and that covenant is still going to be fulfilled. Although Israel was set aside and blinded, God has not taken them out of His program; He will return to finish the Abrahamic covenant.

Les teaches from Genesis 12:1-3 that God spoke to Abraham and promised, "I will make of thee a great nation, I will bless thee, I will make thy name great, thou shalt be a blessing. I will bless them that bless thee, I will curse him that curses thee, and in thee shall all the families of the earth be blessed." Les asks whether God changed His mind and answers no; that covenant is still valid, still true, and still going to be fulfilled. Christ's first coming was to fulfill these promises made to Abraham, Isaac, and Jacob, but Israel rejected it and crucified their Messiah. Yet God did not turn His back on them forever. He set them aside and blinded them, but He has not taken them out of His program. Les explains that God will still come back and finish the Abrahamic covenant.

Genesis 12:2

And I will make of thee a great nation, and I will bless thee, and make thy name great; and thou shalt be a blessing:

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Did God change His mind about the Abrahamic covenant?

No. The Abrahamic covenant remains valid and true; God has not changed His mind. Although Israel was set aside and blinded after rejecting Christ's first coming, God has not removed them from His program and will return to finish and fulfill the Abrahamic covenant.