Spiritism believes Jesus was on Earth as a special envoy from God. He was the most-elevated spirit to incarnate on Earth until his time (and certainly to the present). His preaching was intended to break the traditional and formulaic mindset of the human race, preparing the ground for the evolution of the planet to a higher state. In light of these theses, Spiritism explains the teachings of Christ as veiled hints of what would later be revealed to the world as Spiritism.
For instance, when Jesus said "Think not that I am come to destroy the law", it must be understood that Christ was not revoking, but perfecting or correcting what God had already shown to mankind. According to Spiritism, the teachings of Christ are eternal because they are the very law given by God.
The origin of this law is not the Earth. When he said "My kingdom is not of this world" he was hinting on the heavenly origin of his teachings and the heavenly nature of the work he was doing. He did not come as a human Messiah to save physical lives and restore a temporal kingdom, but to spread the truth about the afterlife so that the spirits of people could evolve faster during their incarnations on Earth.
Christ also hinted on the plurality of inhabited planets, millennia before such a notion became widespread, when he said "In my Father's house are many mansions". As a consequence of it, God's plan is much more complex than mankind can think of: "Except a man be born again, he cannot see the kingdom of God".
Christ's moral is also strongly discussed, especially the Sermon of the Mount. Kardec argues that, assuming that we only live once, the apparent injustice of the world must be a reflection of God's injustice. On the other hand, considering that, through reincarnations, we live many times and that we carry from one life to the next the missions we left unfulfilled, the guilt for the wrongs we did against others, etc. the apparent injustice of the world reflects the compensation of the wrong done in previous lives. Kardec proposes the "Law of Cause and Effect" (an occidentalised version of the Hindu concept of Karma) and reinforces the monstruosity of homicide and suicide as the greatest sins against the law of God.
The Gospel... proposed the notion that adhering to Christ's teachings was a way to get rid of suffering, if not immediately, in a later life. Relying solely on the morality proposed by God we fulfil our missions in the world, stop accumulating guilt by doing wrong to others, and start repairing our past sins. Kardec chose this specific verse because, according to Spiritism, to follow the teachings of Christ is much easier and leads us to more comfort than refusing them: all suffering comes from denying to do what God wants us to, that's why Christ's yoke is light. But the central point of the chapter is that the Spiritist doctrine, being an expansion and a correction of the central teachings of Christ, is the consolation once promised by him. Therefore, "salvation" is not seen as the promotion to a "heaven", but in the literal sense.
Other Christian virtues, like modesty, humility and others are also examined and exhorted. But "Blessed are the meek" is presented in a quite unusual way. This chapter explains why did Christ promise inheritance on earth to the meek. His thesis is that, once everyone follows the teachings of Christ, the present situation (in which most worldly goods are under the control of wicked people) will be reverted. This agrees with chapter 3, in which Kardec demonstrates that Christ did teach that there are many worlds and that, as a consequence, there are more and less evolved worlds. The adoption of Christian principles makes a world evolve and become more pleasant to live.
Divine justice is presented as an extended and more thorough implementation of the Lex talionis: we are submitted to the same things we do unto others so that we learn that they are wrong. So, if we are merciful, God will have mercy on us too. The principle that "Thou shalt love thy neighbour as thyself" is seen, then, also as a protective measure to ensure us against suffering in the future. This chapter also argues that love must be taken into action, otherwise it is not love. It also deals with the separation between the state and the Church as expressed by Christ saying "Render therefore unto Caesar the things which are Caesar's; and unto God the things that are God's."
According to Spiritism, charity must benefit anyone that needs ("Love your enemies"), regardless of faith (a significant moral improvement not yet universalised today). Because of this doctrine, Spiritism should not proselitise; as proselitism could cause people to think that the Spiritist Centres did only help those ready to accept the doctrine. However, the central point of the chapter is that love must be universal, not limited by our preferences or affections. Kardec suggests that Christ may have really meant to say "love even your enemies" (that is, love should be extended to them, not started by them). One curiosity about this chapter is the extensive treaty on duels, because they were popular in France then.
Helping the others is further approached when commenting Christ saying "Let not thy left hand know what thy right hand doeth": The ideal situation is when the help is completely dissociated from any religious practice. In most spiritist centres that adhere to Kardec's teachings, charity has a different schedule than members' meetings and not a word is told about any doctrine, except for a vague invitation to "come around whenever you want to visit us or to seek help if you need" (which does not necessarily imply on coming to the meetings, but merely coming to meet the people you eventually befriend there). Another central teaching, closely related to the above, is that we shouldn't expect people to give us anything in return: to see them better should be our return.
While the Catholic Church usually explains "Many are called, but few are chosen" as an allusion to the minority of Christians that choose to be ordained, Spiritism explains the party of the king (Matthew 22) as a representation of how Israel was called by God but few of the Israelites effectively obeyed the call (and therefore were chosen). The parable is explained as a representation of spiritual life (we are constantly called by God, but every day few of us take heed of the call). This chapter is often used as a justification of why spiritism does not bother to become a major religion, provided that it survives.
Spiritism was accused of lax morality because of its tolerance towards women. Not only did Kardec accept them as equal to men before God but effectively published that the spirits said that a man may chose to live as woman or vice-versa to attain greater improvement. Sex, in Spiritism, is a transitional biological trait that exists among humans, but may be different or absent in other intelligent species of the Universe. Most of the mediums that channelled for Kardec were women, as well as some of the early leaders of Spiritism.
The tolerance extended to marriage as well. When Christ said "Shall man not divide what God has united" is not seen as binding. God has established marriage, it is important for the improvement of mankind now, but it will eventually cease to be . Divorce is possible because the union provided by God is spiritual, not legal. Man cannot break a union that is united by God, so, any union that ends was not united by Him. Therefore, the indissolubility of marriage is relative because there are marriages based on misrepresentation of love, coercion on any or both the nubents or simply by mistake (when a person marries someone and later discovers a sound reason why the wedding should have never taken place). Spiritism accepts divorced people without any discrimination and accepts that they have the right to marry again (although it states that divorce should be an exception, not a rule).
Some other aspects detailed by Christ which become clearer when studied in the light of Spiritism are:
The last two doctrinal chapters of the ''The Gospel According to Spiritism come back to specifically spiritist themes. "Freely ye have received, freely give" establishes the rules why no religious service should be charged at all, as both the word of God and his "miracles" (interventions) are given to us freely. This chapter seems (from the sampled cases studied) to have had two aims: to criticise the Catholic Church for chargin to celebrate masses on behalf of the dead and to instruct true Spiritists not to fall to this, otherwise they would be called charlatans. "Ask, and it shall be given you" is about the importance of praying.