What did Satan not know about the nations he offered to Jesus?
Satan did not know that the nations he offered to Jesus would one day be under Christ's rulership when He rules and reigns. They will come to Him as a result of His sovereignty, not because Satan could give them. He did not understand that future reality.
Les explains that Satan, being a spiritual being, could show Jesus all the kingdoms of the world—past and future empires, from Nebuchadnezzar back to David's kingdom and forward to empires yet to come. He offered Jesus control over all these nations if He would fall down and worship him. But Satan must not have known that one day these same nations will be under Christ's rulership when He rules and reigns. They will come to Him as a result of His sovereignty, not by Satan's offer. Les believes Satan does not know many things and did not understand this future reality.