But we are bound to give thanks to God always for you, brethren beloved by the Lord, because God chose you from the beginning to be saved, through sanctification by the Spirit and belief in the truth. To this he called you through our gospel, so that you may obtain the glory of our Lord Jesus Christ. So then, brethren, stand firm and hold to the traditions which you were taught by us, either by word of mouth or by letter.
Now may our Lord Jesus Christ himself, and God our Father, who loved us and gave us eternal comfort and good hope through grace, comfort your hearts and establish them in every good work and word.
2 Thessalonians 2:13–17 (RSV)
'God chose you from the beginning to be saved, through sanctification by the Spirit and belief in the truth.' When we calculate the universe's age, we are considering numbers so large that the mind struggles. On top of those ages, there is the void out of which the cosmos was called. Time did not exist before God spoke all things into being, and who can begin to speak of what it was before that moment of beginning.
We are cautioned not to dwell too long on these things. Acknowledge their existence, but put no effort in attempting to pull back the veil covering the mystery of creation. Human explanations too easily stray into error when we try to grasp the mind of God.
It is well that we receive the wonder of God's choosing us before all things were. We rest in the peace that God's love has no boundaries, nor has it ever had. We need not concern ourselves with the 'how,' rather live in the 'because' we are loved.
We have been created to be loved and to live out that love.