Gabriel in the Old Testament
In the Old Testament, the angel Gabriel is mentioned only in Daniel. In Daniel 8, Gabriel is first introduced after the vision or prophecy of the sanctuary for the latter days, when the small voice of Purity lifted off the Ulai River (waters of purity) and commanded Gabriel to explain the sanctuary prophecy to Daniel (8:16). This angel appeared again to present the grand four-verse prophecy of the First Advent of the Messiah in Daniel 9, a prophecy which also presented the starting date to count off the 2,300 years for the building of the sanctuary in the latter days.
The angel Gabriel is associated with announcements pertaining to either the sanctuary or First Advent. In all cases, he deals with the spiritual essence of prophecies related to the Christ, Righteousness, Purity. Gabriel shows the divine lovingly ministering in the human.