God's Seventh Day, which is still in progress, is equivalent to not just one but at least seven human millennia or seven thousand years. For God's Own Seventh Day (unlike His first through His sixth days of the Earth's formation week) has not yet terminated.
It is co-extensive with the past and present and future history of man here on Earth – until the arrival of God's Eighth Day. Consequently, man's earthly history would run for seven thousand years, and man's millennial sabbath would consist of the last seventh of God's Seventh Day. Man's millennial sabbath was expected to commence approximately around A.D. 2000. Calvin too seems to have assumed something similar.23