What is the plain language interpretation of “In speaking of a new covenant, he makes the first one obsolete. And what is becoming obsolete and growing old is ready to vanish away. “
But the Gospel is the fulfillment of the Abrahamic Covenant not the Mosaic Law. Read what Paul writes in Galatians 3:
"And the scripture, foreseeing that God would justify the Gentiles through faith, preached before the Gospel unto Abraham , saying, In thee shall all nations be blessed. 9So then they which be of faith are blessed with faithful Abraham...." [note that it says: "with" not "in place of"]
"Christ hath redeemed us [Jews] from the curse of the law .... that the blessing of Abraham might come on the Gentiles through Jesus Christ; that we [Jews] might receive the promise of the Spirit through faith.... And this I say, that the covenant, that was confirmed before of God in Christ, the law, which was four hundred and thirty years after, cannot disannul, that it should make the promise of none effect. For if the inheritance be of the law, it is no more of promise: but God gave it to Abraham by promise."
The Everlasting Gospel is the fulfillment of God's Promise to Abraham not the Mosaic Law. And the gift of the Land of Israel to Abraham's seed is part of that Promise.