I’ve been reading Augustine’s classic The City of God. He argues that the pinnacle of blessing and goodness is found in the certainty of an uninterrupted enjoyment of God. Listen to what he says.
“The beatitude desired by an intelligent being as its proper end will result only from the combination of an uninterrupted enjoyment of that immutable good which is God with deliverance from any doubt or deception concerning the eternity of its continuance.”
God is the immutable good, in Augustine’s thought, and the most blessed state of a human being is in permanent union with this good. Augustine says that blessedness has two sides to it. First, it is marked by an incessant and undisturbed enjoyment of God. Second, it is marked by a certainty that fellowship with God will never be discontinued or broken. The heart of blessing is an eternal and unthreatened communion with the Triune God.
In the context of his discussion he makes an interesting point by contrasting the experience of the angels who fell with the chosen people of God. The angels who rebelled experienced one side of this coin. They knew an intimate and full fellowship with God. However, they did not know the experience of an eternal unbroken fellowship with him. The chosen of God are promised both. The highest blessedness includes the certainty of never losing connection to the immutable good.