Jesus' Attitude toward Adultery
27 “You have heard that it was said,  ‘You shall not commit adultery;’  28 but I tell you that everyone who gazes at a woman to lust after her has committed adultery with her already in his heart. 29 If your right eye causes you to stumble, pluck it out and throw it away from you. For it is more profitable for you that one of your members should perish, than for your whole body to be cast into Gehenna.  30 If your right hand causes you to stumble, cut it off, and throw it away from you. For it is more profitable for you that one of your members should perish, than for your whole body to be cast into Gehenna. 
Jesus' Attitude toward Divorce
31 “It was also said, ‘Whoever shall put away his wife, let him give her a writing of divorce,’  32 but I tell you that whoever puts away his wife, except for the cause of sexual immorality, makes her an adulteress; and whoever marries her when she is put away commits adultery.
Jesus' Attitude toward Oaths
33 “Again you have heard that it was said to them of old time, ‘You shall not make false vows, but shall perform to the Lord your vows,’ 34 but I tell you, don’t swear at all: neither by heaven, for it is the throne of God; 35 nor by the earth, for it is the footstool of his feet; nor by Jerusalem, for it is the city of the great King. 36 Neither shall you swear by your head, for you can’t make one hair white or black. 37 But let your ‘Yes’ be ‘Yes’ and your ‘No’ be ‘No.’ Whatever is more than these is of the evil one.
Love for Enemies
38 “You have heard that it was said, ‘An eye for an eye, and a tooth for a tooth.’  39 But I tell you, don’t resist him who is evil; but whoever strikes you on your right cheek, turn to him the other also. 40 If anyone sues you to take away your coat, let him have your cloak also. 41 Whoever compels you to go one mile, go with him two. 42 Give to him who asks you, and don’t turn away him who desires to borrow from you.
43 “You have heard that it was said, ‘You shall love your neighbor,  and hate your enemy. ’ 44 But I tell you, love your enemies, bless those who curse you, do good to those who hate you, and pray for those who mistreat you and persecute you, 45 that you may be children of your Father who is in heaven. For he makes his sun to rise on the evil and the good, and sends rain on the just and the unjust. 46 For if you love those who love you, what reward do you have? Don’t even the tax collectors do the same? 47 If you only greet your friends, what more do you do than others? Don’t even the tax collectors do the same? 48 Therefore you shall be perfect, just as your Father in heaven is perfect.
5:27 TR adds “to the ancients,”
5:27 Exodus 20:14
5:29 or, Hell
5:30 or, Hell
5:31 Deuteronomy 24:1
5:38 Exodus 21:24; Leviticus 24:20; Deuteronomy 19:21
5:43 Leviticus 19:18
5:43 not in the Bible, but see Qumran Manual of Discipline Ix, 21-26