To be outside of Christ is an absence horrific and unthinkable.
Augustine wrote that every human heart has a God shaped void that needs to be filled. Uniquely, it’s a void that includes everything in the universe, and more. The alienation is utter. Every thought, word, and deed is emptied of meaning apart from Him and every experience loses its character and contemplation. In Him, all things consist.
“He is the image of the invisible God, the firstborn over all creation. For by him all things were created: things in heaven and on earth, visible and invisible, whether thrones or powers or rulers or authorities; all things were created by him and for him. He is before all things, and in him all things hold together. And he is the head of the body, the church; he is the beginning and the firstborn from among the dead, so that in everything he might have the supremacy. For God was pleased to have all his fullness dwell in him, and through him to reconcile to himself all things, whether things on earth or things in heaven, by making peace through his blood, shed on the cross.
Once you were alienated from God and were enemies in your minds because of your evil behavior. But now he has reconciled you by Christ’s physical body through death to present you holy in his sight, without blemish and free from accusation— if you continue in your faith, established and firm, not moved from the hope held out in the gospel. This is the gospel that you heard and that has been proclaimed to every creature under heaven, and of which I, Paul, have become a servant.” Colossians Chapter 1 from verse 15