Having announced that the Lord, according to the declaration of the Prophet, would be born of the house of David, he now says, that the same Lord to fulfil the covenant He made with Abraham will deliver us, because chiefly to these patriarchs of Abraham’s seed was promised the gathering of the Gentiles, or the incarnation of Christ. But David is put first, because to Abraham was promised the holy assembly of the Church; whereas to David it was told that from him Christ was to be born. And therefore after what was said of David, he adds concerning Abraham the words, To perform the mercy promised to our fathers, &c.
Reproduced in full. Translation: Oxford 1841 (Newman), public domain (Public domain).