Upon the heaven, i. e. upon the clouds, to succour thee from thence, by sending thunder and lightning upon thine enemies. See Psalms 18:7, Psalms 68:34, &c. In his excellency, or, in his magnificence, i.e. magnificently, gloriously, and with great majesty as well as power.
Related Commentaries of Deuteronomy 33:26
Deuteronomy 33:26
26 There is none like unto the God of Jeshurun, who rideth upon the heaven in thy help, and in his excellency on the sky.