Deuteronomy 18 ... When thou art come into the land which the Lord thy God giveth thee, thou shalt not learn to do after the abominations of those nations. 10 There shall not be found among you any one that maketh his son or his daughter to pass through the fire, or that useth divination, or an observer of times, or an enchanter, or a witch, 11 Or a charmer, or a consulter with familiar spirits, or a wizard, or a necromancer. 12 For all that do these things are an abomination unto the Lord:and because of these abominations the Lord thy God doth drive them out from before thee. 13 Thou shalt be perfect with the Lord thy God. 14 For these nations, which thou shalt possess, hearkened unto observers of times, and unto diviners:but as for thee, the Lord thy God hath not suffered thee so to do.
15 The Lord thy God will raise up unto thee a Prophet from the midst of thee, of thy brethren, like unto me (says Moses); unto him ye shall hearken; 16 According to all that thou desiredst of the Lord thy God in Horeb in the day of the assembly, saying, Let me not hear again the voice of the Lord my God, neither let me see this great fire any more, that I die not. 17 And the Lord said unto me, They have well spoken that which they have spoken. 18 I will raise them up a Prophet from among their brethren, like unto thee, and will put my words in his mouth; and he shall speak unto them all that I shall command him. 19 And it shall come to pass, that whosoever will not hearken unto my words which he shall speak in my name, I will require it of him.
20 But the prophet, which shall presume to speak a word in my name, which I have not commanded him to speak, or that shall speak in the name of other gods, even that prophet shall die.
21 And if thou say in thine heart, How shall we know the word which the Lord hath not spoken?
22 When a prophet speaketh in the name of the Lord, if the thing follow not, nor come to pass, that is the thing which the Lord hath not spoken, but the prophet hath spoken it presumptuously:
thou shalt not be afraid of him.
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Deuteronomy 19 ... 1 When the Lord thy God hath cut off the nations, whose land the Lord thy God giveth thee, and thou succeedest them, and dwellest in their cities, and in their houses; 2 Thou shalt separate three cities for thee in the midst of thy land, which the Lord thy God giveth thee to possess it. 3 Thou shalt prepare thee a way, and divide the coasts of thy land, which the Lord thy God giveth thee to inherit, into three parts, that every slayer may flee thither.
4 And this is the case of the slayer, which shall flee thither, that he may live:Whoso killeth his neighbour ignorantly, whom he hated not in time past; 5 As when a man goeth into the wood with his neighbour to hew wood, and his hand fetcheth a stroke with the axe to cut down the tree, and the head slippeth from the helve, and lighteth upon his neighbour, that he die; he shall flee unto one of those cities, and live:6 Lest the avenger of the blood pursue the slayer, while his heart is hot, and overtake him, because the way is long, and slay him; whereas he was not worthy of death, inasmuch as he hated him not in time past. 7 Wherefore I command thee, saying, Thou shalt separate three cities for thee.
8 And if the Lord thy God enlarge thy coast, as he hath sworn unto thy fathers, and give thee all the land which he promised to give unto thy fathers; 9 If thou shalt keep all these commandments to do them, which I command thee this day, to love the Lord thy God, and to walk ever in his ways; then shalt thou add three cities more for thee, beside these three:10 That innocent blood be not shed in thy land, which the Lord thy God giveth thee for an inheritance, and so blood be upon thee.
11 But if any man hate his neighbour, and lie in wait for him, and rise up against him, and smite him mortally that he die, and fleeth into one of these cities:12 Then the elders of his city shall send and fetch him thence, and deliver him into the hand of the avenger of blood, that he may die. 13 Thine eye shall not pity him, but thou shalt put away the guilt of innocent blood from Israel, that it may go well with thee.
14 Thou shalt not remove thy neighbour's landmark, which they of old time have set in thine inheritance, which thou shalt inherit in the land that the Lord thy God giveth thee to possess it.
15 One witness shall not rise up against a man for any iniquity, or for any sin, in any sin that he sinneth:at the mouth of two witnesses, or at the mouth of three witnesses, shall the matter be established.
16 If a false witness rise up against any man to testify against him that which is wrong; 17 Then both the men, between whom the controversy is, shall stand before the Lord, before the priests and the judges, which shall be in those days; 18 And the judges shall make diligent inquisition:and, behold, if the witness be a false witness, and hath testified falsely against his brother; 19 Then shall ye do unto him, as he had thought to have done unto his brother:so shalt thou put the evil away from among you.
20 And those which remain shall hear, and fear, and shall henceforth commit no more any such evil among you.
21 And thine eye shall not pity; but life shall go for life, eye for eye, tooth for tooth, hand for hand, foot for foot. (New Testament: Jesus says, 38 Ye have heard that it hath been said, An eye for an eye, and a tooth for a tooth:39 But I say unto you, That ye resist not evil:but whosoever shall smite thee on thy right cheek, turn to him the other also. 40 And if any man will sue thee at the law, and take away thy coat, let him have thy cloke also. 41 And whosoever shall compel thee to go a mile, go with him twain. 42 Give to him that asketh thee, and from him that would borrow of thee turn not thou away.
43 Ye have heard that it hath been said, Thou shalt love thy neighbour, and hate thine enemy. 44 But I say unto you, Love your enemies, bless them that curse you, do good to them that hate you, and pray for them which despitefully use you, and persecute you; 45 That ye may be the children of your Father which is in heaven:for he maketh his sun to rise on the evil and on the good, and sendeth rain on the just and on the unjust. 46 For if ye love them which love you, what reward have ye? do not even the publicans the same? 47 And if ye salute your brethren only, what do ye more than others? do not even the publicans so? 48 Be ye therefore perfect, even as your Father which is in heaven is perfect.
Romans 12 ... 17 Recompense to no man evil for evil. Provide things honest in the sight of all men. 18 If it be possible, as much as lieth in you, live peaceably with all men. 19 Dearly beloved, avenge not yourselves, but rather give place unto wrath:for it is written, Vengeance is mine; I will repay, saith the Lord. 20 Therefore if thine enemy hunger, feed him; if he thirst, give him drink:for in so doing thou shalt heap coals of fire on his head. 21 Be not overcome of evil, but overcome evil with good.
NT church ... We can know God will judge both them and us ... Therefore we try to do what is right in the sight of God in all things.
Jesus said: My kingdom is not of this world ... Jn. 18
Neither is our kingdom of this world.
If it be possible, as much as lieth in you, live peaceably with all men. Romans 12
Certainly there are differences between the Old and New Testaments and instructions ... and there are many things that are the same concepts in Old and New Testaments.
One thing it does for us when we read the Old Testament is show us how God thinks about evil.
At some point we must all appear before the judgment seat of Christ. II Cor. 5 ... We want to be sure the good we do is really good in the sight of God. Through prayer and the Holy Spirit and the scriptures called to our attention by the Holy Spirit, we can know the will of God for us in each matter at hand.