The slowing eras of cosmological expansion are generally justified as being due to gravity. How is gravitational slowing justified in a flat or nearly Flat universe. If the universe were closed or if our Hubble sphere were the complete universe, gravitational slowing is a logical consequence, If one takes the Hubble sphere as a sample volume of a larger universe, the inward gravitational acceleration at the Hubble scale is approximately c^2/R. So one might reason that a mass at the distance of the Hubble scale would be subjected to a deceleration in the range of c^2/R. But that ignores the gravitational pull of the Hubble sphere that has its center on the same line of action at a distance of 2R.