I understand that sin is sin, whether it's a little lie or adultery, and that God forgives all sins when we repent and confess, but are their degrees of sin? I ask this because my mother committed adultery, divorced my father after many years of marriage, and married the person she committed adultery with.  


True, all sin is an offense against a Holy God.  However, there are severity of sins.  Let me explain.  If a teenager speaks harshly to their mother, it is a sin.  But if that same teenager were to slap their mother, then it is a more serious offense, and hurts the mother's heart more deeply.  Both offenses are sin, but one has even a greater offense and act of defiance.  When we sin against God it is like a slap of defiance in His face, but a sin of adultery against the partner of one's youth is a very hard slap of defiance.  A husband may think of an immoral thought, and that is sin, but to actually commit an act of adultery against his wife is very serious.

God forgives the sins of Christians when they truly repent from their hearts.  Actually, their sins (past, present, and future) were all forgiven at the cross, and the sin we actually confess has already been paid for, but when we actually commit the sin, then we offend God our Father, and interrupt the sweet fellowship with Him.  The Father wants us to repent and restore the relationship of sweetness.  Our eternal salvation was never in question (if we were truly saved).
However, since God's purpose in saving us was to make us more like Christ, so that we can bring honor and glory to Christ, then He (as a perfect loving Father) must discipline us because of the sin.  For your mother to have committed adultery was a serious sin against God, and she did not desire to repent, for she continued on in  divorcing her husband and then marrying this other person.  If when this is all over, she decides that she has done wrong and confesses her sin, then yes, God forgives her, and starts the restoration process.  However, there most likely will be consequences of the sin and some discipline.  Remember, as Christians we represent Christ, and so the sin not only brings shame upon us, but also upon Christ and His church.  Discipline of the repentant Christian may also serve as an example to others, and also show the world that God does discipline His children--If He doesn't then He is not a perfect Father. 
For a Christian to leave their marriage partner, is a statement that loudly says they do not trust that God can solved whatever problem or need that they have in their marriage.  God's will is for Christians to stay married no matter what, and to trust and pray to Him for help in that relationship.
Most likely, if your mother is truly a Christian, then God will have to discipline her for her sin, and it will be in love, but it most likely will be painful.  He can use physical suffering, emotional pain, etc., but whatever, it is designed to teach her not to do that again, and for others to take heed, and to vindicate Christ and his Church in the world.
King David committed an awful sin of adultery and murder, and suffered greatly for it, even though he was forgiven.  God says of David, that he was a man after my own heart, but He had to discipline him for his sin against God and the shame brought to God's people.
I can honestly say that I have been tempted in my own life to commit some serious sins, but have always reflected on God's Word and the fact that as a loving Father He would have to discipline me, and frankly I didn't want to experience that or cause pain to my loved ones, thus I could turn from the temptations.  The secret is to stay close to the Lord by reading His Word and praying daily.

Added to Bible Bulletin Board's "Tony Capoccia's Questions and Answers" by:

Tony Capoccia
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