If you are talking about incest, and I'll assume you are, there is no gentle way to say this....you are sinning against God.
The New Testament does not mention incest because to these people, incest was such a big offense to God (as outlined in the OT) that they didn't need to mention it specifically. However, it can be called sexual immorality which is mentioned several times in the NT.
The OT does mention incest though it doesn't use that term:
[FONT="]Leviticus 18:6 says, "None of you shall approach to any that is near of kin to him, to uncover their nakedness: I am the Lord."
In Genesis 19, the Bible records what happens to a family where two daughters have children with their father. The resulting people...Ammonites and Moabites were not allowed into God's temple:
[/FONT][FONT="]"In Genesis 19, the Bible records the sad account of a backslidden man named Lot. In Sodom, he loses his testimony, his credibility, his influence, his sons-in-law, and finally his wife. He and his two daughters are living in a cave.(vs.30) The two daughters agree to a plan to get him drunk so they can sleep with him and preserve seed of their father.(vs.32)
It is interesting to note that the seed was none other than the infamous Moabites and Ammonites! (vs. 37-38) There are too many Scriptures to list to show their rebellious attitude towards the nation of Israel. Deut. 23:3 says, 'An Ammonite or Moabite shall not enter into the congregation of the Lord: even to their tenth generation shall they not enter into the congregation of the Lord for ever.' "[/FONT]
Leviticus has some strict rules about sexual relations. And though we (Christians) are not under the ceremonial law, we are still under the morality part...which Jesus repeated in the NT:
11 “‘If a man has sexual relations with his father’s wife, he has dishonored his father. Both the man and the woman are to be put to death; their blood will be on their own heads.
12 “‘If a man has sexual relations with his daughter-in-law, both of them are to be put to death. What they have done is a perversion; their blood will be on their own heads.
13 “‘If a man has sexual relations with a man as one does with a woman, both of them have done what is detestable. They are to be put to death; their blood will be on their own heads.
14 “‘If a man marries both a woman and her mother, it is wicked. Both he and they must be burned in the fire, so that no wickedness will be among you.
15 “‘If a man has sexual relations with an animal, he is to be put to death, and you must kill the animal.
16 “‘If a woman approaches an animal to have sexual relations with it, kill both the woman and the animal. They are to be put to death; their blood will be on their own heads.
17 “‘If a man marries his sister, the daughter of either his father or his mother, and they have sexual relations, it is a disgrace. They are to be publicly removed from their people. He has dishonored his sister and will be held responsible.
18 “‘If a man has sexual relations with a woman during her monthly period, he has exposed the source of her flow, and she has also uncovered it. Both of them are to be cut off from their people.
19 “‘Do not have sexual relations with the sister of either your mother or your father, for that would dishonor a close relative; both of you would be held responsible.
20 “‘If a man has sexual relations with his aunt, he has dishonored his uncle. They will be held responsible; they will die childless.
21 “‘If a man marries his brother’s wife, it is an act of impurity; he has dishonored his brother. They will be childless.
22 “‘Keep all my decrees and laws and follow them, so that the land where I am bringing you to live may not vomit you out. 23 You must not live according to the customs of the nations I am going to drive out before you. Because they did all these things, I abhorred them. 24 But I said to you, “You will possess their land; I will give it to you as an inheritance, a land flowing with milk and honey.” I am the Lord your God, who has set you apart from the nations.
" God has never approved of indiscriminate sexual activity outside of the marriage relationship in any age of human history. As one writer has noted,
'the fundamental problem with incest [and other extra-marital sexual sins] is that it strikes at the soundness of the family. And since the family is central to God’s purposes and work on earth, his judgment on this practice is fierce'".
People will point out that Adam and Eve's children had to have children together ....but there are things that was allowed early on in the history of mankind that God did not allow later.
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