A full understanding of the psychological and spiritual import of this question requires great wisdom to provide and to receive.
I have written some excellent books on the subject of marriage and relationships, and have written and lectured extensively on fatherhood, the duties of a husband, and the profundities of marriage for over 22 years.
There are reasons why a man must have honor, fidelity, and do his duty. But I'm not telling you anything new. The fact that a man must be honorable, patient, kind, and virtuous--you already knew this in your heart, didn't you? If you are not honorable, it is because you are selfish or have a lot of growing up to do.
Of course we all start off our relationship selfish. But we all should also grow up. And growing up means learning to be unselfish. In fact, I have always said that marriage is not a pleasure party. The purpose of marriage is to have children and a family. We can be selfish before we get married, but once married we begin to see our weaknesses and selfishness that we did not know we had before being within the walls of marriage.
Holy matrimony is a framework within which to learn to be unselfish.
Perhaps now you can see why it is best to wait until marriage. Marriage is a sign of fidelity and honor. Should you, as the man, give in to the temptation of the popular culture or the lady in question, to not wait until marriage, in her eyes it shows that you are easy to tempt and that you do not have impeccable honor.
If she is like many other women, she may have been taken advantage of by other men and has not been loved properly. She already judges men, and now she will judge you too as being just like all the rest.
Later on in the relationship, you will find that she does not respect you, may have contempt for you, does not trust you, and you will have hell to pay. I am not saying that things can't be worked out, but it may take 20 or 30 years for her to learn to respect you, and this only if you truly change for the better. Sadly many men remain selfish and unaware, and do not know why their weakness harms their family.
You see, a man's authority is goodness, patience, understanding, the courage of conviction, and the respect of others for his virtue. If you are weak or violent, if you worship women more than God, or if you put your wife on a pedestal, your family will have contempt for you and will end up in rebellion.
When you are weak or wrong, and when you do not uphold virtue and principle, you have no authority. No wonder you are held in contempt and your family is in rebellion.
Anger and violence are wrong and also show moral weakness. Some men use violence to try to get back their authority, but violence is wrong and shows moral weakness. They will hate you.
In regard to your question, here I will just give part of the short answer.
If you just cheated on your wife, there is a very powerful reason for telling her: Basic decency and disease prevention.
There are many sexually transmitted diseases and they are rampant. Any contact outside of the bounds of marital fidelity carries the risk of contracting and spreading one or more of the many STD's.
You owe it to her to advise her so that she can monitor her health and partner with her medical provider to make sure that she is free from disease (or receive appropriate treatment, if through you, she has acquired a disease).
Just be aware of the fact that she may decide to divorce you.
If you cheated on her many years ago, and you are both disease free, then there are other factors involved. I will address this these other factors in another blog or book, or in private consultation.
Here I will just give a couple of preliminary thoughts. If you cheated on her long ago, whether to tell her or not depends, in part, on your reason for telling her. You must be thoroughly versed in the psychology of it and be prepared to do what is right, but also factor in what makes sense and is reasonable, rather than just emotionally saying things that might be misunderstood or forever after used against you.
I am a pastor, so my advice to individual people who consult with me about this topic may surprise some. I say "It all depends" because some men, instead of confessing and making things right in their heart before their Creator, get on their knees before their wife, which is akin to begging her (instead of God) for forgiveness.
His display of wrongness and weakness is a tremendous temptation to her to puff up in judgment, and also to feel superior and righteous by comparison.
If she is judgmental of men, based on experience with men beginning with her father who was not there for her and then other weak men she has known, your confession will only confirm what she already suspected--that you are just another weak selfish man who is a user--and she may judge you forever.
If you have changed for the better over the years--you saw your selfishness and you saw that your wife and children need you to be there for them--and now you have mended your ways, a weak admission of some long ago dalliance will serve no purpose other than tempt her to judge you and never be able to forget what you told her. She might "forgive you" for guilt relief, but secretly resent you for making her having to deal with it.
I am not saying not to be honest, but I am also warning you that what you say to her can and will be used against you. Women tend to have a memory a mile long when it comes to a man's mistakes.
So first, look at your motivation, become very well centered, and have a crystal clear understanding of what a man's, husband's and father's role is before you dump your sins in her lap.
Whether it just happened or happened a long time ago, it would undoubtedly be wise to read my paperback book The Myths and Mysteries of Marriage - Making Relationships Work. You need a thorough grounding about what is at stake and just what the duties of the husband and father are.
If perchance you are interested in becoming a better husband and father, you probably need some good fatherly advice--the kind you would get from a wise father who also loves and respects women and who knows what their true needs are. You are unlikely to find such understanding in the popular culture. My book might help
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