How beautiful, then, the marriage of two Christians, two who are one in hope, one in desire, one in the way of life they follow, one in the religion they practice. They are as brother and sister, both servants of the same Master. Nothing divides them, either in flesh or in spirit. They are, in very truth, two in one flesh; and where there is but one flesh there is also but one spirit. They pray together, they worship together, they fast together; instructing one another, encouraging one another, strengthening one another, side by side they visit God's church and partake of God's Banquet; side by side they face difficulties and persecution, share their consolations. They have no secrets from one another; they never shun each other's company; they never bring sorrow to each other's hearts. Unembarrassed they visit the sick and assist the needy. They give alms without anxiety; they attend the Sacrifice without difficulty; they perform their daily exercises of piety without hindrance. They need not be furtive about making the Sign of the Cross, nor timorous in greeting the brethren, nor silent in asking a blessing of God. Psalms and hymns they sing to one another, striving to see which one of them will chant more beautifully the praises of their Lord. Hearing and seeing this, Christ rejoices. To such as these He gives His peace. Where there are two together, there also He is present; and where He is, there evil is not.
These, then, are the thoughts which the Apostle in that brief expression of his has left for our consideration. Recall them to your mind, if ever there should be need to do so. Use them to strengthen yourself against the bad example which certain women give you. In no other way than this are Christians permitted to many—and, even if they were, it would not be the prudent thing to do.
Taken from Tertullian (c. 160-220), “To His Wife” in Treatises on Marriage and Remarriage, ACW Series, no. 13, trans. William P. LeSaint, S.J. (Westminster, MD: Newman Press, 1951): 35-36.