There are alot of people who are in your situation, yet most live in ignorance of the adulterous aspect of their second marriage. I assume you read my investigation on the subject of divorce and remarriage at http://www.bcbsr.com/topics/marry.html Though I don't give much advice there concerning the remarried, only that I liken such situations to a serial form of polygamy and as such as one would advise a parallel polygamist, so also a serial polygamist. For let's say a Middle Eastern Muslim, who had many wives, converted to Christianity. And then in studying the Bible he came across:
Mark 10:6-9 "But at the beginning of creation God 'made them male and female.' 'For this reason a man will leave his father and mother and be united to his wife, and the two will become one flesh.' So they are no longer two, but one. Therefore what God has joined together, let man not separate."
He may receive the revelation from the Spirit and his eyes opened to the fact that the two become one, not the three or four become one. And also in Timothy and Titus a requirement for an elder is to be the husband of but one wife, not two or three. Formerly he was unaware of his sinfulness in practicing polygamy, but having been made aware what should he do? It can be a bit of a conundrum in that he made promises and commitments to women he shouldn't have and yet the Bible also teaches of the characteristic of the righteous being "He who swears to his own hurt and does not change" Ps 15:4 The resolution may be to maintain those aspects of the promises which are not sinful, but discontinue those aspects which are sinful.
The most important aspect of developing applications concerning disputable areas is to follow your conscience in the light of what God has revealed to you. Concerning a clear conscience Paul writes Timothy with some instructions then saying, "Now the purpose of the commandment is love from a pure heart, from a good conscience, and from sincere faith ..." 1Tim 1:5 and in Acts he says, "I myself always strive to have a conscience without offense toward God and men." Acts 24:16 Violating one's conscience can shipwreck one's faith as Paul writes, "wage the good warfare, having faith and a good conscience, which some having rejected, concerning the faith have suffered shipwreck," 1Tim 1:18,19 And he advocates that when it comes to gray areas people should not only follow their conscience, but also avoid violating the conscience of another. (1Cor 8:12; 1Cor 10:29) By this he is not talking about not making other people feel guilty such as in revealing to them their sinfulness. What he means is not to provoke other people to violate their own conscience in which God has developed particular convictions in them.
This poses an interesting problem if one considers divorcing out of an adulterous relationship. For the spouse, or many in the Christian community may view the divorce itself as sinful or provoke them into casually considering divorcing their own spouses for truly inappropriate reasons. Consider the case of eating meats sacrificed to idols which Paul had to deal with both in Romans 14 and 1Cor 8-10. "If your brother is distressed because of what you eat, you are no longer acting in love. Do not by your eating destroy your brother for whom Christ died. Do not allow what you consider good to be spoken of as evil." Romans 14:15,16 So here is a catch-22: Should polygamists divorce even if they don't reckon their relationship adulterous in order not to violate the conscience of those who do reckon such relationships adulterous. Or should those who do reckon them adulterous not divorce so as to not violate the conscience of those who reckon that divorce itself is sinful? But It seems to me Paul was talking about making compromises which don't violate anyone's conscience. In the context the priority is first to clear one's own conscience and not be living a sinful life as the Holy Spirit and the Word of God direct through one's conscience.
When you remarried you sinned unintentionally, not being aware of God's perspective concerning such situations. Not that such is an excuse for even in the Law of Moses it is written:
"Now if the whole congregation of Israel sins unintentionally, and the thing is hidden from the eyes of the assembly, and they have done something against any of the commandments of the LORD in anything which should not be done, and are guilty; when the sin which they have committed becomes known ... the priest shall make atonement for them, and it shall be forgiven them." Leviticus 13,14,20
Of course under the New Covenant even intentional sins are forgiven if one repents and puts their faith in Christ. But the point I wanted to make here is that sin is still sin even if unintentional. And once one becomes aware of their sin, action should be taken. Some may advocate simply asking for forgiveness but continuing on in the same sin. That doesn't seem to me to be characteristic of genuine repentance. It seems to me that if a person knows they are sinning then they should stop sinning. Notice God's attitude in this rhetorical question given in Jeremiah 7:9,10 "Will you steal and murder, commit adultery and perjury, burn incense to Baal and follow other gods you have not known, and then come and stand before me in this house, which bears my Name, and say, 'We are safe'— safe to do all these detestable things?"
But as I said many even in the Christian community are unaware of their own sinful behavior in many areas. Perhaps even all of us have such blind spots. I would be careful not to judge the ignorant, for God does make a distinction between intentional and unintentional sin. Consider that in the Old Testament that while the more overt forms of adultery had the death penalty associated with them, there was no penalty for polygamy. Polygamy was not even explicitly mentioned as a sin. It was not until the New Testament that Jesus revealed alot of things being sinful which formerly were hidden or only could be inferred as sinful from the Old Testament. But it seems clear to me as I mentioned in the study guide that while polygamy and more overt forms of adultery are in the same category, they are treated as different degrees. As such I don't even shun polygamist Christians who have yet to develop a conscious awareness of their sin. Though no doubt I make them uncomfortable when I teach on the subject. Nonetheless truth has priority in relationships and Paul warns concerning more overt sinful behavior, "Do you not know that the unrighteous will not inherit the kingdom of God? Do not be deceived. Neither fornicators, nor idolaters, nor adulterers, nor homosexuals, nor sodomites, nor thieves, nor covetous, nor drunkards, nor revilers, nor extortioners will inherit the kingdom of God." 1Cor 6:9,10 and not to fellowship with alleged Christians who practice such behavior. "I have written to you not to keep company with anyone named a brother, who is sexually immoral, or covetous, or an idolater, or a reviler, or a drunkard, or an extortioner——not even to eat with such a person." 1Cor 5:11, such as in the case of 1Cor 6:1 "It is actually reported that there is sexual immorality among you, and such sexual immorality as is not even named among the Gentiles——that a man has his father’s wife!" But as I pointed out concerning 1Tim and Titus that polygamy only disqualifies one from eldership, but apparently is not reckoned a basis for disfellowship.
I think that Bible is purposely unclear as to what a Christian polygamist should do, as indeed it is unclear on many practical areas of the life in order that we walk not simply by the letter but by the Spirit. Walk in accordance with the guidance of the Spirit as you derive specific applications of the Bible in maintaining a good conscience before God and you will not fulfill the lusts of the flesh.
By the way this is not arm chair theology to me. My wife divorced me a few years after she had run away with a married man. Yet even in my case in order to maintain a good conscience in view of my convictions I will not remarry. For "For the woman who has a husband is bound by the law to her husband as long as he lives." Rom 7:2 and "even if she does depart, let her remain unmarried or be reconciled to her husband." 1Cor 7:11 And that's another issue. For what if your former wife wanted to reconcile with you? Would you remarry her?
The Berean Christian Bible Study Resources