1 Corinthians 13-15 (Douay-Rheims)
And if any woman hath a husband that believeth not, and he consent to dwell with her, let her not put away her husband. [14]For the unbelieving husband is sanctified by the believing wife; and the unbelieving wife is sanctified by the believing husband: otherwise your children should be unclean; but now they are holy
Vintage, it is good to take a picture at what precedes and what follows:1 Corinthians, Chapter 7, 10-15 (Douay-Rheims) [10] But to them that are married,
not I but the Lord commandeth, that the wife depart not from her husband. [11] And if she depart, that she remain unmarried, or be reconciled to her husband. And let not the husband put away his wife. [12]
For to the rest I speak, not the Lord. If any brother hath a wife that believeth not, and she consent to dwell with him, let him not put her away. [13] And if any woman hath a husband that believeth not, and he consent to dwell with her, let her not put away her husband. ... [14]
For the unbelieving husband is sanctified by the believing wife; and the unbelieving wife is sanctified by the believing husband: otherwise your children should be unclean; but now they are holy. ... [15] But if the unbeliever depart, let him depart. For a brother or sister is not under servitude in such cases. But God hath called us in peace.
.
The end (aim) of a Christian Marriage is the sanctification of the spouses, and as a result of that the sanctification of the offspring, the focus being Unity with God Himself. That is the be-all-and-end-all of our state in life. So we do our best to achieve it.
.
I would like to write more but I am called away.