וַתֹּאמֶר֩ דְּבֹרָ֨ה אֶל־בָּרָ֜ק ק֗וּם כִּ֣י זֶ֤ה הַיּוֹם֙ אֲשֶׁר֩ נָתַ֨ן יְהוָ֤ה אֶת־סִֽיסְרָא֙ בְּיָדֶ֔ךָ הֲלֹ֥א יְהוָ֖ה יָצָ֣א לְפָנֶ֑יךָ וַיֵּ֤רֶד בָּרָק֙ מֵהַ֣ר תָּב֔וֹר וַעֲשֶׂ֧רֶת אֲלָפִ֛ים אִ֖ישׁ אַחֲרָֽיו׃
And Deborah said unto Barak: ‘Up; for this is the day in which the LORD hath delivered Sisera into thy hand; is not the LORD gone out before thee?’ So Barak went down from mount Tabor, and ten thousand men after him.
Metzudat David on Judges
Up: That is to say, don't delay yourself, standing here to fortify yourself on the mountain
Radak on Judges
Has not the Lord gone out before you: It is like its translation (in the Targum) - "did not the angel of the Lord go out before you to make you successful."