Albert Barnes on Galatians 3:14

That the blessing of Abraham. The blessing which Abraham enjoyed to wit, that of being justified by faith.

Might come on the Gentiles.

As well as on the Jews. Abraham was blessed in this manner before he was circumcised, Rom 4:11, and the same blessing might be imparted to others also who were not circumcised. See this argument illustrated Rom 4:10.

Through Jesus Christ. Since he has been made a curse for all, and since he had no exclusive reference to the Jews or to any other class of men, all may come and partake alike of the benefits of his salvation.

That we might receive the promise of the Spirit. That all we who are Christian converts. The promise of the Spirit, or the promised Spirit, is here put for all the blessings connected with the Christian religion. It includes evidently the miraculous agency of the Holy Spirit; and all his influences in renewing the heart, in sanctifying the soul, and in comforting the people of God. These influences had been obtained in virtue of the sufferings and death of the Lord Jesus in the place of sinners, and these influences were the sum of all the blessings promised by the prophets.

(a) "blessing of Abraham" Rom 4:9,16 (b) "promise of the Spirit" Isa 44:3, Eze 36:27, Joel 2:28,29 (*) "through" "by"