Tertullian, to his wife, around 200AD:
What a bond is this: two believers who share one hope, one desire, one discipline, the same service! There is no distinction of spirit or flesh, but truly they are two in one flesh. Where there is one flesh, there is also one spirit. Together they pray... together they fast, teaching each other, exhorting each other, supporting each other. Side by side in the church of God and at the banquet of God, side by side in difficulties, in times of persecution, and in times of consolation. Neither hides anything from the other, neither shuns the other, neither is a burden to the other. They freely visit the sick and sustain the needy... Seeing and hearing this, Christ rejoices. He gives them His peace. Where there are two He also is present; and where He is , there is no evil."