Dayspring

This is another term that Zacharias uses in Luke 1 and which is used to describe Jesus. This is the definition of dayspring: dayspring |ˈdāˌspri ng |
noun poetic/literary
dawn; the first light of day
The bible dictionary defines it as daybreak.

The word is only used twice in the scriptures:

Luke 1:78

Through the tender mercy of our God; whereby the dayspring from on high hath visited us,

Job 38:12

Hast thou commanded the morning since thy days; and caused the dayspring to know his place;