Because of Christ, we are a seed and heir of Abraham  -  Galatians 3:29

And if ye be Christ's, then are ye Abraham's seed, and heirs according to the promise.

Christ is the seed of Abraham and the inheritance to him was fulfilled in Christ. When sinners put their trust in Christ, they become one in Him. Thus, they become Abraham’s seed and, in Christ, inherit all of God’s blessings.