A Biblical perspectiveTheology ·Saturday March 30, 2019 @ 17:02 EDT (link)
There are some sins that are over and done with a single act; they remain in the past, and the doer can seek forgiveness, having repented with the intent not to repeat the sin.
Divorce, or leaving your spouse even before or without legal involvement, is certainly not a sin like that. It is rather one that has to be maintained and chosen day by day. It is not one choice to do evil and then you ask God for forgiveness (never mind that you should also ask your spouse and children, if any, for forgiveness also) and he forgives you and it's over. No; it is a continuing choice, day by day, to do evil and not instead attempt to restore the family you tried to tear apart.
You may be forgiven for the initial act, but if you have not changed your mind and heart about it, you commit it over and over again. That is not repentance.
Therefore to him that knoweth to do good, and doeth it not, to him it is sin. —James 4:17
That change of heart—repentance, to use God's term—need not perhaps involve returning to the spouse you left right away, but that should be considered the goal, as soon as possible, as you discuss individually and perhaps through counseling the issues that prompted the sin, whether simple greed or things that the departing spouse may have been unhappy about in the marriage.
But if the unbelieving [spouse] depart, let him depart. A brother or a sister is not under bondage in such cases: but God hath called us to peace. —1 Corinthians 7:15
Standard disclaimer that only God knows the heart and whether someone is or is not one of his.
Whosoever abideth in him sinneth not: whosoever sinneth hath not seen him, neither known him. —1 John 3:6
Matthew Henry expands on the above verse in his Commentary as follows:
Those that abide in Christ abide in their covenant with him, and consequently watch against the sin that is contrary thereto. They abide in the potent light and knowledge of him; and therefore it may be concluded that he that sinneth (abideth in the predominant practice of sin) hath not seen him (hath not his mind impressed with a sound evangelical discerning of him), neither known him, hath no experimental acquaintance with him.
One can, sorrowfully and regretfully, but soundly, conclude that someone that continues in the sin of departure from their spouse, without willingness to reconcile, and especially in the absence of clear sin on the part of the other (such as adultery or violence), continues in sin, and question whether they have ever known the Lord. In turn, this would appear to free the spouse left behind to remarry should he or she so choose, once the decision of the other is clear, and it would be to their conscience as to how much time they might allow to pass or the efforts they would make to reconciliation, which efforts I would hope would be, for Christian, extensive.
There is no joy in the destruction of a relationship that God values so much that he has used it to illustrate that of Christ and his church.