The Enchiridion by St. Augustine
Chapter 62.--By the Sacrifice of Christ All Things are Restored, and Peace is Made Between Earth and Heaven.
And, of course, the holy angels, taught by God, in the eternal contemplation of whose truth their happiness consists, know how great a number of the human race are to supplement their ranks, and fill up the full tale of their citizenship. Wherefore the apostle says, that |all things are gathered together in one in Christ, both which are in heaven and which are on earth.| The things which are in heaven are gathered together when what was lost therefrom in the fall of the angels is restored from among men; and the things which are on earth are gathered together, when those who are predestined to eternal life are redeemed from their old corruption. And thus, through that single sacrifice in which the Mediator was offered up, the one sacrifice of which the many victims under the law were types, heavenly things are brought into peace with earthly things, and earthly things with heavenly. Wherefore, as the same apostle says: |For it pleased the Father that in Him should all fullness dwell: and, having made peace through the blood of His cross, by Him to reconcile all things to Himself: by Him, I say, whether they be things in earth, or things in heaven.|