Commentaries:
Jamieson, Fausset, and Brown
see it—The Septuagint for "it," has "the salvation of God." So Luke 3:6 (compare Luke 2:30, that is, Messiah); but the Evangelist probably took these words from Isaiah 52:10.
for—rather, "All flesh shall see that the mouth of Jehovah hath spoken it" [BENGEL].
Other Jamieson, Fausset, and Brown entries containing Isaiah 40:5:
Psalms 97:6
Isaiah 35:2
Isaiah 40:6
Isaiah 58:14
Malachi 3:1
Luke 3:6
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