GABRIEL (gā'brĭ-ĕl, Heb. gavrî’ēl, man of God, Gr. Gabriēl). An angel mentioned four times in Scripture, each time bringing a momentous message. He interpreted to Daniel the vision of the ram and the goat (Dan.8.16-Dan.8.17). In Dan.9.21-Dan.9.22 he explained the vision of the seventy weeks. Gabriel announced to Zechariah the birth of John, forerunner of the Messiah (Luke.1.11-Luke.1.20); and he was sent to Mary with the unique message of Jesus’ birth (Luke.1.26-Luke.1.38). His credentials are the ideal for every messenger of God: “I am Gabriel. I stand in the presence of God, and I have been sent to speak to you and to tell you this good news” (Luke.1.19). The Bible does not define his status as an angel, but he appears in the Book of Enoch (Luke.9.1-Luke.9.62, Luke.20.1-Luke.20.47, 40) as an archangel.
The angel plays a role in the Lucan account of the Incarnation, as Gabriel is the messenger who announces the birth of John the Baptist to his father the priest, Zechariah, in the Temple (Luke 1:19) and the birth of the Messiah to the Virgin Mary (1:26). His action in both places and the acceptance of his message is similar to the appearance recorded in Daniel. He indicates his authority as one who stands in the presence of the Almighty and thus follows His bidding and bears divine authority for His message. The mythical encrustation of the ages has not dimmed the simple narrative of the angelic announcement, and the Scripture envisions no such creature as the artists of the Renaissance often depicted, a half-man and half-bird derived from late Gr. sculpture. A most interesting aspect is the rarity with which such heavenly visitations are mentioned in the Bible, and in each of the four cases are directly connected to the fulfillment of the Messianic promise. Speculations on the mechanism and details of these angelic announcements have troubled the Church throughout the ages.
International Standard Bible Encyclopedia (1915)
(gabhri’-el, "Man of God"; Gabriel):
The name of the angel commissioned to explain to Daniel the vision of the ram and the he-goat, and to give the prediction of the 70 weeks (Da 8:16; 9:21).
In the New Testament he is the angel of the annunciation to Zacharias of the birth of John the Baptist, and to Mary of the birth of Jesus (Lu 1:19,26).
Though commonly spoken of as an archangel, he is not so called in Scripture. He appears in the Book of Enoch (chapters 9, 20, 40) as one of 4 (or 6) chief angels. He is "set over all powers," presents, with the others, the cry of departed souls for vengeance, is "set over the serpents, and over Paradise, and over the cherubim." He is prominent in the Jewish Targums, etc.