Simply looking with lust at a woman is adultery
Mat 5:27-30 You have heard that it was said by those of old times, ‘You shall not commit adultery’: 28 But I say to you that whoever looks upon a woman, to lust after her has committed adultery with her already in his heart. 29 And if your right eye causes you to offend, pluck it out, and cast it from you: For it is better for you that one of your members should perish, and not that your whole body should be cast into hell. 30 And if your right hand causes you to offend, cut it off and cast it from you; for it is better for you that one of your members should perish, and not that your whole body be cast into hell.
Jesus retains Moses’ allowance for divorce from the bride who is discovered to have fornicated prior to the wedding
Mat 5:31-32 It has been said, ‘Whoever puts away his wife, let him give her a formal notice of divorce’: 32 But I say to you, That whoever puts away his wife, except for the cause of fornication, causes her to commit adultery: And whoever marries her that is divorced commits adultery.
Deu 22:13-29 If any man takes a wife, and goes in to her, and hates her, 14 and gives occasion to speak against her, and brings up an evil name upon her, and says, ‘I took this woman, and when I came to her, I did not find her a virgin’: 15 Then the father of the damsel, and her mother, shall take and bring forth the tokens of the damsel’s virginity to the elders of the city in the gate: 16 And the damsel’s father shall say to the elders, ‘I gave my daughter to this man to wife, and he hates her; 17 and lo, he has given occasions of speech against her, saying, “I did not find your daughter to be a virgin” (“I discovered that she has fornicated prior to our wedding”); and yet these are the tokens of my daughter’s virginity.’ And they shall spread the cloth before the elders of the city. 18 And the elders of that city shall take that man and chastise him; 19 and they shall fine him one hundred shekels of silver as a penalty, and give them to the father of the damsel, because he has brought up an evil name upon a virgin of Israel: And she shall be his wife; he may not put her away all his days. 20 But if this thing is true, and the tokens of virginity are not found for the damsel: 21 Then they shall bring out the damsel to the door of her father’s house, and the men of her city shall stone her with stones such that she dies: Because she has worked folly in Israel, to play the whore in her father’s house (she has fornicated prior to wedding a husband): So shall you put evil away from among you. 22 If a man is found lying with a woman married to a husband, then both of them shall die, both the man that lay with the woman, and the woman: So shall you put away evil from Israel. 23 If a damsel that is a virgin is betrothed to a husband, and a man finds her in the city, and lies with her; 24 then you all shall bring them both out to the gate of that city, and all you shall stone them with stones such that they die; the damsel, because she did not cry out, being in the city; and the man, because he has humbled his neighbor’s wife: So you shall put away evil from among you. 25 But if a man finds a betrothed damsel in the field, and the man forces her, and lies with her: Then only the man that lay with her shall die. 26 But you shall do nothing to the damsel; there is no sin worthy of death in the damsel: For as when a man rises against his neighbor, and slays him, even so is this matter: 27 For he found her in the field, and the betrothed damsel cried out, and there was no one to save her. 28 If a man finds a damsel that is a virgin, who is not betrothed, and lays hold on her, and lies with her, and they are found out; 29 then the man that laid with her shall give fifty shekels of silver to the damsel’s father, and she shall be his wife; because he has humbled her, he may not put her away all his days.
Jesus rejects Moses’ allowance for remarriage after divorce
Mat 19:3-12 The Pharisees also came to Him, tempting Him, and saying to Him, “Is it lawful for a man to put away his wife for every cause?” 4 And He answered and said to them, “Have you not read, that He which made them at the beginning ‘made them male and female,’ 5 and said, ‘For this reason a man shall leave father and mother, and shall cleave to his wife: And those two shall be one flesh?’ 6 For which reason they are no longer two, but one flesh. Therefore, what God has joined together, let not man separate.” 7 They said to Him, “Why then did Moses command to give a formal notice of divorce, and to put her away?” 8 He said to them, “Moses permitted you to put away your wives because of the hardness of your hearts: But from the beginning it was not so. 9 And I say to you, Whoever puts away his wife, except if it be for fornication, and marries another, commits adultery: And whoever marries her that is put away commits adultery.” 10 His disciples said to Him, “If this is the case for a man with his wife, it is not good to marry.” 11 But He said to them, “Not all men can receive this saying, except those to whom it is given. 12 For there are some eunuchs, which were so born from their mother’s womb: And there are some eunuchs, which were made eunuchs by men: And there are eunuchs who have made themselves eunuchs for the kingdom of heaven’s sake. He that is able to receive it, let him receive it.”
Jesus’ clear teaching: no exception
Mar 10:1-12 And He arose from that place, and came into the borders of Judea by the far side of the Jordan: And the people went with Him again; and as He was accustomed to, He taught them with repetition. 2 Then the Pharisees came to Him, and asked Him, “Is it lawful for a man to put away his wife?” testing Him. 3 And He answered and said to them, “What did Moses command you?” 4 And they said, “Moses permitted to write a formal notice of divorce, and to put her away.” 5 And Jesus answered and said to them, “For the hardness of your heart he wrote you this precept. 6 But from the beginning of the creation God ‘made them male and female.’ 7 For this reason a man shall leave his father and mother, and cleave to his wife; 8 and the two shall be one flesh: So then they are no longer two, but one flesh. 9 Therefore what God has joined together, let not man separate.” 10 And in the house His disciples asked Him again about the same matter. 11 And He said to them, “Whoever puts away his wife, and marries another, commits adultery against her. 12 And if a woman puts away her husband, and marries another, she commits adultery.”
Luk 16:18 Whoever puts away his wife, and marries another, commits adultery: And whoever marries her that is put away from her husband commits adultery.
Adulterers will not inherit the kingdom of God, nor will fornicators, without repenting
1Co 6:9-11 TKJU 9 Do you not know that the unrighteous shall not inherit the kingdom of God? Do not be deceived: Neither fornicators, nor idolaters, nor adulterers, nor effeminate, nor abusers of themselves with mankind, 10 nor thieves, nor covetous, nor drunkards, nor revilers, nor extortioners, shall inherit the kingdom of God. 11 And such were some of you: But you are washed, but you are sanctified, but you are justified in the name of the Lord Jesus, and by the Spirit of our God.
God will judge adulterers
Heb 13:4 TKJU Marriage is honorable in everyone, and the bed undefiled: But whore-mongers and adulterers God will judge.
The church must judge unrepentent sinners who are called brothers
1Co 5:1-13 It is commonly reported that there is fornication among you, and such fornication as is not even named among the Gentiles, that one should have his father’s wife. 2 And you are puffed up, and have not rather mourned, that he who has done this deed might be taken away from among you. 3 For I indeed, as absent in body, but present in spirit, have already judged, as though I were present, concerning him that has so done this deed, 4 in the name of our Lord Jesus Christ, when you are gathered together, and my spirit, with the power of our Lord Jesus Christ, 5 to deliver such a one to Satan for the destruction of the flesh, that the spirit may be saved in the day of the Lord Jesus. 6 Your boasting is not good. Do you not know that a little leaven leavens the whole lump? 7 Therefore purge out the old leaven, that you may be a new lump, as you are unleavened. For even Christ our passover is sacrificed for us: 8 Therefore let us keep the feast, not with old leaven, neither with the leaven of malice and wickedness; but with the unleavened bread of sincerity and truth. 9 I wrote to you in a letter not to keep company with fornicators: 10 Yet not completely with the fornicators of this world, or with the covetous, or extortioners, or with idolaters; for then you would need to go out of the world. 11 But now I have written to you not to keep company, if any man that is called a brother is a fornicator, or covetous, or an idolater, or a reviler, or a drunkard, or an extortioner; not to eat with such an one. 12 For what have I to do with judging those that also are outside? Do you not judge those that are inside? 13 But those that are outside God judges. Therefore put away from among yourselves that wicked person.
The church must judge and excommunicate unrepentent sinners who are called brothers
1Co 5:1-13 It is commonly reported that there is fornication among you, and such fornication as is not even named among the Gentiles, that one should have his father’s wife. 2 And you are puffed up, and have not rather mourned, that he who has done this deed might be taken away from among you. 3 For I indeed, as absent in body, but present in spirit, have already judged, as though I were present, concerning him that has so done this deed, 4 in the name of our Lord Jesus Christ, when you are gathered together, and my spirit, with the power of our Lord Jesus Christ, 5 to deliver such a one to Satan for the destruction of the flesh, that the spirit may be saved in the day of the Lord Jesus. 6 Your boasting is not good. Do you not know that a little leaven leavens the whole lump? 7 Therefore purge out the old leaven, that you may be a new lump, as you are unleavened. For even Christ our passover is sacrificed for us: 8 Therefore let us keep the feast, not with old leaven, neither with the leaven of malice and wickedness; but with the unleavened bread of sincerity and truth. 9 I wrote to you in a letter not to keep company with fornicators: 10 Yet not completely with the fornicators of this world, or with the covetous, or extortioners, or with idolaters; for then you would need to go out of the world. 11 But now I have written to you not to keep company, if any man that is called a brother is a fornicator, or covetous, or an idolater, or a reviler, or a drunkard, or an extortioner; not to eat with such an one. 12 For what have I to do with judging those that also are outside? Do you not judge those that are inside? 13 But those that are outside God judges. Therefore put away from among yourselves that wicked person.