The Jesus Conspiracy by Kersten & Gruber
This is a book from 1994 published by Barnes & Noble. There is an excerpt online that is critical of Paulinism versus the teachings of Jesus. While I don't agree with everything in this book nor the notions Jesus preached in India which Kersten endorses (see link), the following section contains informative and thoughtful contrasts between Paul and Jesus. This is taken from an excerpt hosted at this online link:
Although there are several most delightful passages in the texts of Paul, Christianity has his narrow-minded fanaticism to thank for numerous detrimental developments, which are diametrically opposed to the spirit of Jesus: the intolerance towards those of different views (for example, Gal. 1:9; marked hostility to the body and the 1 Cor. 16:22; Tit 3:10), the consequently low view of woman (1 Cor. 6:18, 7:1-2, 7:38, 12:23, Gal. 5:17, Eph. 5:3-5; Col. 3:3, 5-6), and especially the fatally flawed attitude towards Nature (Col. 2:8; 1 Cor. 2:14; Eph. 5:19; Phil. 3:20).
According to the teaching of Paul, the human individual is unable to attain Salvation and atonement before God by any good works of his own, or by any change however good (Rom. 3:24, 3:28, 9:11, 9:16; 1 Cor. 1:29; Gal. 2:16): 'For by grace are ye saved through faith; and that not of yourselves: it is the gift of God: Not of works, lest any man should boast.' Consequently the precondition for the action of God's Grace is the acceptance of the Pauline teaching on Grace; that means membership of the Church of Paul.
Based on Paul, the Christian churches today still teach that the Salvation of all was perfectly finished once and for all by the blood sacrifice of Jesus on the Cross, and that men would have absolutely nothing to contribute to it, apart from simply accepting this kind of Salvation in a single act of conversion (baptism). Nothing more is needed to reach the purpose and goal of life, for Jesus has already done all that is needful for us anyway, as our representative. This leads on to the idea that any attempt to participate in Salvation by one's own effort can be taken as a belittling of the service rendered by Jesus, and even as an original sin, as a futile attempt at self-salvation. According to this view anyone holding different beliefs, however exemplary the life he has led (such as Gandhi), is considered to be lost if he does not accept the Cross sacrifice for himself, in other words if he refuses to profess the Pauline Christianity.
Naturally it is an attractive and tempting offer, to be released from all responsibility for one's actions and the consequences of bad acts and thoughts, in a simple and comfortable way, by a few splashes of water. The ominous consequences of this form of Salvation doctrine finally lead to a kind of trade in indulgences, where the offender can count in advance on the annulment of his guilt before God and his conscience. Therefore even thc worst misdemeanours against any fellow creatures have no consequence.
But this idea is completely alien to the teaching of Jesus. It was far from his mind, to form a hierarchical bureaucracy with laws and scriptural doctors, with belief in the letter of the law and arguments about interpretations, with cult and image worship, with 'churchianity' and claims to exclusive rights to bless. He wanted to preach the intimacy between the Divine and the human individual, and not self-aggrandising channels of official instances set up by self-righteous administrators of God. Jesus was certainly educated enough to be able to write his message himself, if he had considered it to be a valid method. But instead of this he presented his teaching by living it as an example: the renunciation of egoistic thinking and acting, unbiased care for all living beings, giving and sharing, the greatest possible tolerance towards people of other convictions, taking on the suffering of others and feeling compassion for them, in other words unlimited love in action for all fellow beings.
What we today refer to as Christianity is a misinterpretation and twisting by Paul of the true teaching of Jesus. Knowledge about this misinterpretation, and the doctrine of Salvation by the vicarious sacrifice of Jesus which is given a central place in it, has long belonged to the truisms of modern theological and church historical research. Unfortunately until now these truths have been suppressed by all possible means, and therefore they have not penetrated to the foundations. Even at the start of the eighteenth century the English philosopher Lord Bolingbroke (1678-1751) noticed two completely different religions in the New Testament, that of Jesus and that of Paul. Kant, Lessing, Fichte and Schelling also clearly distinguished between the teaching of Jesus and what the 'apostles' made of it. A large number of reputed modern theologians have come to acknowledge this fact.
One can now ask why it took 2000 years before the Pauline Salvation idea could be shown as absurd by these modern methods, by considering the legacy left by Jesus. One possible answer is that there has never been such an urgent need for an honest study of the heritage of Jesus, to finally get back to the true message of his teaching.
One item I don't agree with is they apparently question whether Jesus understood he was dying to pay the atonement for others. This clearly was Jesus's words at the time of the Last Supper. So unless the authors are skeptical of that statement, that ends that issue.