The New John Gill Exposition of the Entire BibleLuke 1:67
And his father Zacharias was filled with the Holy Ghost,
&c.] With a spirit of prophecy, as his wife Elisabeth had been
before, (Luke 1:41)
saying; the following things, relating to the
Messiah, his incarnation and redemption by him; to the accomplishing
of the covenant, oath, promise and mercy of God to his people; and
to his son, the forerunner of Christ; and to his work and office, in
the various parts and branches of it, which he should perform.
Whence it appears, that the following song is of divine inspiration;
and that Zacharias spake it as he was moved by the Holy Ghost, as
the prophets of old did.