Commentary for Deuteronomy 2:28

אכל בכסף תשברני, “sell me food in exchange for money!” The meaning is “in the event that I need to buy supplies.” Similarly, מים בכסף תתן לי ושתיתי, רק אעברה ברגלי, “water in exchange for money give me so that I may drink it,; only let me pass through on foot.” Moses referred to the armies marching though Sichon’s territory. From this verse you can deduce that when the prophet Zecharyah had depicted G’d as standing on the Mount of Olives (Zecharyah 14,4) this was a reference to the heavenly hosts and soldiers. (The author discussed this in detail on Genesis 6,6).