And the LORD came down in a cloud, and spake unto him, and took of the spirit that was upon him, and gave it unto the seventy elders: and it came to pass, that, when the spirit rested upon them, they prophesied, and did not cease.
Then God appeared in a cloud and talked to Moses. He took some of the power from Moses and gave it to seventy older people. When they received this power, they were able to predict future events and didn't stop doing so.