A Spiritually Mixed Marriage
As explained in 1 Corinthians 7:13-14, if you find yourself married to a non-Christian
because of a marriage prior to you giving your life to Christ, God regards your
marriage as holy. If, however, as a Christian, you deliberately married a
non-Christian, you have made things very difficult for yourself, but you
have not committed an unforgivable sin. To marry someone not committed to the true God is such a grave offense that in the Old Testament couples committing this sin were required to divorce. I don’t think this is required under the New Testament but it vividly highlights the gravity of marrying a non-Christian. In order to receive forgiveness,
you must acknowledge that you sinned by entering this marriage and you must
decide that if you had your time over again you would not commit that sin i.e. you would not have married that person. God
sees your heart, and if you are genuine he will forgive you, make your
marriage holy, and support you in your struggle to resist temptations that
result from having a non-Christian partner.