There is so much difference between the message of Paul and Jesus that it is impossible to provide a full answer as you can write a book about the differences. I have provided below a small highlight, of the basic changes, not the complicated matters such as, inherent sin etc… Unfortunately, Christianity now is the religion of Paul not Jesus.
Jesus teaches that the Law has not been annulled
Mt 5:17 Think not that I am come to destroy the law, or the prophets: I am not come to destroy, but to fulfil. 18 For verily I say unto you, Till heaven and earth pass, one jot or one tittle shall in no wise pass from the law, till all be fulfilled.*
Luke 16:17 - 17 It is easier for heaven and earth to disappear than for the least stroke of a pen to drop out of the Law.
Mt 19:17 And he said unto him, Why callest thou me good? there is none good but one, that is, God: but if thou wilt enter into life, keep the commandments.
Revelations 2:14 - 14But I have a few things against you, because some of you hold to the teaching of Balaam, who taught Balak to place a stumbling block before the Israelites so they would eat food sacrificed to idols and commit sexual immorality.
Revelations 2:20 - 20But I have this against you: You tolerate that woman Jezebel, who calls herself a prophetess. By her teaching she misleads My servants to be sexually immoral and to eat food sacrificed to idols.
Acts 15:20 - 20Instead, we should write and tell them to abstain from food polluted by idols, from sexual immorality, from the meat of strangled animals, and from blood.
Acts 15:29 - 29You must abstain from food sacrificed to idols, from blood, from the meat of strangled animals, and from sexual immorality. You will do well to avoid these things. Farewell.
Acts 21:21 - 21But they are under the impression that you teach all the Jews who live among the Gentiles to forsake Moses, telling them not to circumcise their children or observe our customs.
Acts 21:25 - 25As for the Gentile believers, we have written to them our decision that they must abstain from food sacrificed to idols, from blood, from the meat of strangled animals, and from sexual immorality.” 26So the next day Paul took the men and purified himself along with them. Then he entered the temple to give notice of the date when their purification would be complete and the offering would be made for each of them
“Did not Moses give you the law, and yet none of you keepeth the law” (John7:19)
Matthew 5:17-19 - 17 Do not think that I have come to abolish the Law or the Prophets; I have not come to abolish them but to fulfill them. 18 For truly, I say to you, until heaven and earth pass away, not an iota, not a dot, will pass from the Law until all is accomplished. 19Therefore whoever relaxes one of the least of these commandments and teaches others to do the same will be called least in the kingdom of heaven, but whoever does them and teaches them will be called great in the kingdom of heaven.
Genesis 17:10-12 - 10 This is My covenant, which you shall keep, between Me and you and your descendants after you: every male among you shall be circumcised. 11 And you shall be circumcised in the flesh of your foreskin, and it shall be the sign of the covenant between Me and you. 12 And every male among you who is eight days old shall be circumcised throughout your generations, including a slave who is born in the house or who is bought with money from any foreigner, who is not of your descendants.
JAMES 2:26 Just as the body is dead without breath, so also faith is dead without good works
Luke 16:17 It is easier for heaven and earth to disappear than for the least stroke of a pen to drop out of the Law.
Paul teaches that it was annulled.
1Cor 8:4 As concerning therefore the eating of those things that are offered in sacrifice unto idols, we know that an idol is nothing in the world, and that there is none other God but one.
Rom 7:6 But now we are delivered from the law, that being dead wherein we were held; that we should serve in newness of spirit, and not in the oldness of the letter.
Rom 10:4 For Christ is the end of the law for righteousness to every one that believeth.
Gal 3:13 Christ hath redeemed us from the curse of the law, being made a curse for us: for it is written, Cursed is every one that hangeth on a tree:
1 Corinthians 8:7 - 7 But not everyone possesses this knowledge. Some people are still so accustomed to idols that when they eat sacrificial food they think of it as having been sacrificed to a god, and since their conscience is weak, it is defiled. 8 But food does not bring us near to God; we are no worse if we do not eat, and no better if we do.
1 Corinthians 10:25-27 25 Eat anything sold in the meat market without raising questions of conscience, 26 for, “The earth is the Lord’s, and everything in it.”27 If an unbeliever invites you to a meal and you want to go, eat whatever is put before you without raising questions of conscience.
Gal. 2:16 - A man is not justified by observing the law, but by faith in Jesus Christ, because by observing the law no one will be justified.
Romans 3:28 For we maintain that a person is justified by faith apart from
the works of the law.
2 Timothy 1:11 And of this gospel I was appointed a herald and an apostle and a teacher.
“Remember that Jesus Christ of the seed of David was raised from the dead according to my gospel:” 2 Timothy 2:8
Gal. 5:4 "You who are trying to be justified by law have been alienated from Christ; you have fallen away from grace".
Ephesians 2:15 - 15 Having abolished in his flesh the enmity, even the law of commandments contained in ordinances; for to make in himself of twain one new man, so making peace;
Romans 7:3 - 3 So then if, while her husband liveth, she be married to another man, she shall be called an adulteress: but if her husband be dead, she is free from that law; so that she is no adulteress, though she be married to another man.
Galatians 3:19 - 19 Wherefore then serveth the law? It was added because of transgressions, till the seed should come to whom the promise was made; and it was ordained by angels in the hand of a mediator.
2 Corinthians 3:14 - 14 But their minds were blinded: for until this day remaineth the same vail untaken away in the reading of the old testament; which vail is done away in Christ.
Romans 3:28 - King James Version
28 Therefore we conclude that a man is justified by faith without the deeds of the law.
Jesus without financial reward.
Mt 10:8 Heal the sick, cleanse the lepers, raise the dead, cast out devils: freely ye have received, freely give.
1Cor 9:11 If we have sown spiritual things for you, is it a great thing if we reap your material things?
Jesus bless them - Mt 5:44 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;
Paul says unbelievers are cursed - 1Cor 16:22 If anyone does not love the Lord Jesus Christ, let him be accursed. O Lord, come!
Who do you follow
Jn 10:27 My sheep hear My voice, and I know them, and they follow Me.
Matthew 23:8 - 8 But you are not to be called rabbi, for you have one teacher, and you are all brothers.
John 14:15: “If you love Me, you will keep My commandments."
1Cor 4:16 Therefore I urge you, imitate me. [KJV=”Wherefore I beseech you, be ye followers of me.”]
1 Corinthians 4:15 - 15 Even if you had ten thousand guardians in Christ, you do not have many fathers, for in Christ Jesus I became your father through the gospel.
Faith and confession
Paul: Rom 10:9 That if thou shalt confess with thy mouth the Lord Jesus, and shalt believe in thine heart that God hath raised him from the dead, thou shalt be saved.
1Cor 12:3 Wherefore I give you to understand, that no man speaking by the Spirit of God calleth Jesus accursed: and that no man can say that Jesus is the Lord, but by the Holy Ghost.
Mt 7:21 Not every one that saith unto me, Lord, Lord, shall enter into the kingdom of heaven; but he that doeth the will of my Father which is in heaven. 22 Many will say to me in that day, Lord, Lord, have we not prophesied in thy name? and in thy name have cast out devils? and in thy name done many wonderful works? 23 And then will I profess unto them, I never knew you: depart from me, ye that work iniquity [NKJV = lawlessness].
Luke 6:46 And why call ye me, Lord, Lord, and do not the things which I say?
Who will judge on judgement day
Paul says followers
1Cor 6:2 Do ye not know that the saints shall judge the world? and if the world shall be judged by you, are ye unworthy to judge the smallest matters? 3 Know ye not that we shall judge angels? how much more things that pertain to this life?
Roman 11:26: And so all Israel will be saved, as it is written: “The Deliverer will come from Zion; He will remove godlessness from Jacob.
(Paul refers to but changes it - Isaiah 59:20-21: “The Redeemer will come to Zion, to those in Jacob who repent of their sins,” declares the LORD.
Jn 5:22 For the Father judges no one, but has committed all judgment to the Son.
Paul seeks to please men and to be “all things to all men”.
1Cor 9:20 And unto the Jews I became as a Jew, that I might gain the Jews; to them that are under the law, as under the law, that I might gain them that are under the law; 21 To them that are without law, as without law, (being not without law to God, but under the law to Christ,) that I might gain them that are without law. 22 To the weak became I as weak, that I might gain the weak: I am made all things to all men, that I might by all means save some.
1Cor 10:33 Even as I please all men in all things, not seeking mine own profit, but the profit of many, that they may be saved.
Luke 6:26 Woe unto you, when all men shall speak well of you! for so did their fathers to the false prophets.
Luke 16:15 And he said unto them, Ye are they which justify yourselves before men; but God knoweth your hearts: for that which is highly esteemed among men is abomination in the sight of God.
Jn 5:41 I receive not honour from men.
Eph 2:14 For He Himself is our peace, who has made both one, and has broken down the middle wall of separation, 15 having abolished in His flesh the enmity, that is, the law of commandments contained in ordinances, so as to create in Himself one new man from the two, thus making peace, 16 and that He might reconcile them both to God in one body through the cross, thereby putting to death the enmity. 17 And He came and preached peace to you who were afar off and to those who were near.
“In the day when God shall judge the secrets of men by Jesus Christ according to my gospel.” – Romans 2:16
“According to the grace of God which is given unto me, as a wise masterbuilder, I have laid the foundation, and another buildeth thereon.” – 1 Corinthians 3:10
“Remember that Jesus Christ of the seed of David was raised from the dead according to my gospel:” – 2 Timothy 2:8
1 Corinthians 10:23 - 23 All things are lawful; but not all things are expedient. All things are lawful; but not all things edify.
Mark 1:14 14 Now after John was delivered up, Jesus came into Galilee, preaching the gospel of God,
Matthew 4:23 - 23 And [a]Jesus went about in all Galilee, teaching in their synagogues, and preaching the [b]gospel of the kingdom, and healing all manner of disease and all manner of sickness among the people.
Mt 10:34 Think not that I am come to send peace on earth: I came not to send peace, but a sword.
Matthew 23:8 - 8 But you are not to be called rabbi, for you have one teacher, and you are all brothers.
Jn 7:16 Jesus answered them, and said, My doctrine is not mine, but his that sent me.
God of living or dead
Jesus says - Luke 20:38 For he is not a God of the dead, but of the living: for all live unto him.
Mk 12:27 He is not the God of the dead, but the God of the living: ye therefore do greatly err.
Paul - Rom 14:9 For to this end Christ both died, and rose, and revived, that he might be Lord both of the dead and living.
5 And that prophet, or that dreamer of dreams, shall be put to death; because he hath spoken to turn you away from the LORD your God, which brought you out of the land of Egypt, and redeemed you out of the house of bondage, to thrust thee out of the way which the LORD thy God commanded thee to walk in. So shalt thou put the evil away from the midst of thee.
Follow Jesus not Paul