Even an unbelieving husband or wife is sanctified by a believing partner.
For the unbelieving husband is sanctified because of the wife, and the unbelieving wife because of her husband.
Believers, take not for friends unbelieving infidels rather than believers.
He always has been and I have always been a stubborn, unbelieving old mule!
But if your unbelieving spouse abandons you, you are not obliged endlessly to pursue him or her.