Luke 1:55

“As he spake to our fathers, etc.] To David, of whose family Mary was; and to Jacob, or Israel, of whose stock she was; and to Isaac, in whom the seed was to be, called; and particularly, to Abraham and to his seed for ever: not his natural, but his spiritual seed; both among Jews and Gentiles, to the end of the world; to these God promised this mercy of a Saviour and Redeemer, and to these he performs it, and will to all generations.”

“As he spake to our fathers--The sense requires this clause to be read as a parenthesis. (Compare Mic 7:20; Psa 98:3). for ever--the perpetuity of Messiah's kingdom, as expressly promised by the angel (Luk 1:33).”

“As he spake to our fathers ... - That is, He has dealt mercifully with the children of Israel, according as He promised Abraham, Isaac, and Jacob. The promise particularly here referred to is that respecting the Messiah which was now about to be fulfilled; but there is no doubt that there was also included the promises respecting all the other mercies which had been conferred on the children of Israel. See Genesis 22:17-18. Forever - These words are to be referred to the preceding verse - “in remembrance of His mercy” forever, “as he spake,” etc. They denote that the “mercy of God” manifested to His people should be had in everlasting remembrance. There is a striking similarity between this…”

“To his seed - His spiritual seed: all true believers. Luke 1:56”

“Gen 12:3, Gen 17:19, Gen 22:18, Gen 26:4, Gen 28:14; Psa 105:6-10, Psa 132:11-17; Rom 11:28, Rom 11:29; Gal 3:16, Gal 3:17 Luke 1:57”