What a sad and difficult situation this must be for you. Adultery is a serious mortal sin and you are right in being very concerned. Before we address your questions, let us first consider the gravity of your sister’s actions. What is adultery? The Catechism of the Catholic Church states the following: “Adultery refers to marital infidelity. When two partners, of whom at least one is married to another party, have sexual relations – even transient ones – they commit adultery”(CCC #2380).
It continues by stating, “Adultery is an injustice. He who commits adultery fails in his commitment. He does injury to the sign of the covenant which the marriage bond is, transgresses the rights of the other spouse, and undermines the institution of marriage by breaking the contract on which it is based. He compromises the good of human generation and the welfare of children who need their parents' stable union” (CCC #2381).
Adultery was forbidden by God as one of the Ten Commandments – “You shall not commit adultery” (Exodus 20:14). Jesus also condemned it by teaching that not only is committing of the act sinful, but also the desire for it. His teaching was clear: “Everyone who looks at a woman with lust has already committed adultery with her in his heart” (Matthew 5:28).
Knowing then what injurious and grave sin adultery is, is it a sin for you to listen to your sister speak about her involvement with this man? The answer is that it depends on the circumstances. Perhaps your sister is really in need of someone to confide in and is subconsciously looking for someone to talk her out of it. Knowing that adultery is wrong and an offense against God, you have a moral obligation to try to help your sister to realize the error of her ways. This must be done with charity but firmness and conviction. After all, she is your sister, not a stranger. You have a close relationship with her that allows the opportunity to speak to her about this. To say nothing would definitely be wrong. If you saw your sister about to jump off a cliff to her death, would you stand by and say, “It’s none of my business?” Your sister is in a similar situation in that she is committing mortal sin and is in danger of spiritual death.
We must consider also that this situation could possibly present an occasion of sin for you as well. However, because you say that you are very much against it, then it would not be as serious an occasion for sin for you as it might be for a person who perhaps has been guilty of such sin in the past. As Christians, we are under moral obligation to avoid all sin, but some situations make it very difficult for us, as with you listening to your sister speak about her adulterous relationship. Certainly it would be wrong for you to sit by and pretend that it is acceptable. You should pray to God for the strength and wisdom to know when to speak and what to say. He will help you.
It is possible too that in being there for her, you will be able to lead her closer to God by your own good example of Christian living. Often, this can be the best witness. But never should you forget your duty as a follower of Christ to help a fellow brother or sister. When you ask if it is sinful to pray for her happiness even if it means involvement with this man, you must realize that her true happiness can never be with this man as long as he is married to another woman. Only when we follow and obey the law of God, which is based on His infinite love for us, can we be truly happy, fulfilled, and free. Speak to her often of God and His love for her. Jesus forgave the adulterous woman but then said, “Go, and from now on do not sin anymore” (John 8:11).
© Copyright 2001 Grace D. MacKinnon
Grace MacKinnon is a syndicated columnist and public speaker on Catholic doctrine. Readers are welcome to submit questions about the Catholic faith to: Grace MacKinnon, 1234 Russell Drive #103, Brownsville, Texas 78520. Questions also may be sent by e-mail to: [email protected]. You may visit Grace online at www.DearGrace.com.
