How Do We Know if God is Living in Us?

The Apostle John writes ” If we love one another God dwells in us and his love is brought to perfection in us.” Begin to love; you will be perfected. Have you begun to love? God has begun to dwell in you. As John continues “In this we know that we abide in him and he in us, because he has given us his Spirit.” How do we know that “he has given us of his Spirit”? Ask your heart; if it is filled with love, you have received the Spirit of God.

—Augustine, Commentary on the Epistle of John, 8.12