'Seventy' in the Bible

This whole land will be a desolation and a horror, and these nations will serve the king of Babylon seventy years.

‘Then it will be when seventy years are completed I will punish the king of Babylon and that nation,’ declares the Lord, ‘for their iniquity, and the land of the Chaldeans; and I will make it an everlasting desolation.

“For thus says the Lord, ‘When seventy years have been completed for Babylon, I will visit you and fulfill My good word to you, to bring you back to this place.