In what realm do Jesus and Satan both operate?
Both Jesus and Satan operate in the spiritual realm. Even though Christ was present in the flesh during the temptation, He also exists in the spiritual, and Satan is a spiritual being. From that spiritual vantage point, Satan could show Jesus all the kingdoms of the world, past and future.
Les explains that Jesus and Satan are both spiritual, even though Christ is here in the flesh and also in the spiritual. From the spiritual concept, Satan could let Jesus look all the way back to Nebuchadnezzar, maybe even back to David's great kingdom, and forward to all the great empires yet to come in human history. Satan offered Jesus control over all these nations if He would fall down and worship him. Les also notes that Satan must not have known that one day these same nations will be under Christ's rulership when He rules and reigns as a result of His sovereignty.