Like many reformers, Erasmus saw the leaders of his Church abusing their powers, and he endeavored to drive the popes and cardinals and bishops back to the earlier, purer days of the Church. In Julius Exclusis, he ridiculed Pope Julius II and accused him of corruption. He saw the Church leaders desiring too much power and, in Enchiridion Militis Christiani, wrote that they denied Jesus in that desire: "It is always a source of amazement to me that popes and bishops so indiscreetly wish to be called lords or masters when Christ forbade his disciples to be called either."  Erasmus thought the leaders sacrificed their spiritual duties to their greed and lust and insulted Christianity by their actions.
Erasmus also argued that the corrupt clergy reduced religious ceremonies to mere habits and emphasized complicated dogma. He instead advocated that Christians strive to emulate Jesus. The sacraments and Gospels should be gateways to Jesus, but the Church undermined them with excess ritual. Historian Johan Huizinga, in his Erasmus and the Age of the Reformation, recognized Erasmus's desire for simplicity:
He found society, and especially religious life, full of practices, ceremonies, traditions and conceptions, from which the Spirit seemed to have departed. He does not reject them offhand and altogether: what revolts him is that they are so often performed without understanding and right feeling. But to his mind, highly susceptible to the foolish and ridiculous things, all that sphere of ceremony and tradition displays itself as a useless, nay, a hurtful scene of human stupidity and selfishness. 
(16)Erasmus feared that the ceremonies outweighed the meanings in the Catholic Church; he wanted to teach people to revere and think about those meanings.
Erasmus's teaching rejected the material means to salvation so often peddled to the laity, emphasizing that such things distracted from discovering Jesus. Like Luther, he was particularly scornful of popular Catholic attitudes (and the clergy's exploitation of those attitudes) toward saints, writing in 1503,
Now there are not a few who are given over to the veneration of saints, with elaborate ceremonies. Some, for example, have a great devotion to St. Christopher. Provided his statue is in sight, they pray to him almost every day. Why do they do this? It is because they wish to be preserved from a sudden and unprovided-for death that day. There are others who have a great devotion to St. Roch.... This has gone to the extent that each nation has its own. Among the French St. Paul is esteemed, among us Germans St. Jerome has a special place. . . . This kind of piety, since it does not refer either our fears or our desires to Christ, is hardly a Christian practice. 
The saints were good, and one should respect their teachings, but "we kiss the shoes of the Saints and their dirty handkerchiefs and we leave their books, their most holy and efficacious relics, neglected."  Erasmus asked his Christians to return to the primary, to their Christ.
Before Luther became known in the Holy Roman Empire, Erasmus preached that the truest link to Jesus was through the scriptures and that every Christian should study the life of Jesus in those scriptures. He did not want Christians to obey the clergy blindly; he wanted them to know why they were Christians. As he wrote in "Paraclesis," the 1516 foreword to his translation of the New Testament,
I absolutely dissent from those people who don't want the holy scriptures to be read in translation by the unlearned-as if, forsooth, Christ taught such a complex doctrine that hardly anyone outside a handful of theologians could understand it, or as if the chief strength of the Christian religion lay in people's ignorance of it. . . . The first step is simply to understand. Many will ridicule, no doubt, but some will be intrigued. As a result, I would hope that the farmer might chant a holy text at his plow, the spinner sing it as she sits at her wheel, the traveler ease the tedium of his journey with tales from the scripture. Let all conversation between Christians draw from this source, for almost all of us are as our daily conversations form us. 
For Erasmus, the most important method of learning to be a Christian was reading the story of the Christ in the scriptures. In 1516 Erasmus emphasized the (17)scripture and the laity's access to it, anticipating and influencing Luther's demand for a return to scripture.
Luther had admired Erasmus and had used his teachings, but in the 152Os, the two began to debate about reform. As Luther strayed farther from the Catholic Church, Erasmus clung to it, because even as they held some similar ideas, their philosophical bases differed: Erasmus was somewhat skeptical and not as confident to proclaim that he knew the truths of God as was the dogmatic Luther. In The Free Will, Erasmus confessed his skepticism:
so great is my dislike of assertions that I prefer the views of the sceptics wherever the inviolable authority of Scripture and the decision of the Church permit. ... And as a matter of fact, I prefer this natural inclination to one I can observe in certain people who are so blindly addicted to one opinion that they cannot tolerate whatever differs from it. 
Luther, however, displayed his intolerant, dogmatic attitude, the attitude that allowed him to succeed in attacking the Church, when he attempted to refute Erasmus's statement in The Bondage of the Will:
Not to delight in assertions is not the mark of a Christian heart. Indeed, one must delight in assertions to be a Christian at all! To avoid misunderstandings, let me define assertion. I mean a constant adhering to and affirming of your position, avowing and defending it, and invincibly persevering in it. ... Far be it from us Christians to be sceptics and academics. 
Erasmus was not always confident that he knew the grand truths that Luther claimed to know, so he would not sacrifice his more important ideas to those wavering questions.
Leaders of religious revolutions must allow no one to challenge their bases for revolting, but Erasmus's skepticism allowed him to have an open mind. Some questions in the Church he considered inessential to salvation, so he chose not to argue about them.  Neither did he argue about things beyond human intellectual capacity. Because he thought some questions could not be answered with certainty, he was willing to tolerate debate, and if proven wrong, he would have conceded:
Even if I have understood what Luther discusses, it is altogether possible that I am mistaken. Therefore, I merely want to analyze and not judge, to inquire and not to dogmatize. I am ready to learn from anyone who advances something more accurate or more reliable. 
(18)Erasmus's willingness to debate, his deliberate avoidance of definite assertions, appalled Luther, for Luther saw danger in anything less.
To rend the Catholic Church and throw western civilization into years of chaos, the leaders of the Reformation had to be willing to sacrifice peace for their ideals; Erasmus, however, had a gentle nature. Huizinga characterized Erasmus as "a delicate soul in all his fibres," writing, "In the moral sphere, Erasmus's delicacy is represented by his great need of friendship and concord, his dislike of contention. With him, peace and harmony rank above all other considerations, and he confesses them to be the guiding principles of his actions."  Erasmus found peace and harmony in books and words and tried to use them to influence Christians to forsake the material and ceremonial and live as Christians.
In contrast to the gentle Erasmus, Luther's words, his polemical style of violent imagery created an combative atmosphere; he argued militantly. He showed this militancy in his attack on Erasmus in The Bondage of the Will: "I hope you credit Luther with some acquaintance with and judgement in the sacred writings. If not, beware and I'll wring the admission from you!"  He showed this militancy in his dual attack on the Catholic Church and lax Protestant preachers in his Catechism:
Now that they are free from the useless, bothersome babbling of the Seven Hours, it would be fine if every morning, noon, and evening they would read, instead, at least a page or two from the Catechism, the Prayer Book, the New Testament, or something else from the Bible and would pray the Lord's Prayer for themselves and their parishioners. In this way they might show honor and gratitude to the Gospel, through which they have been delivered from so many burdens and troubles, and they might feel a little shame because, like pigs and dogs, they remember no more of the Gospel than this rotten, pernicious, shameful, carnal liberty. 
The words Luther used, wring, pernicious, rotten, suggested to those who supported him that Luther wanted them to take an uncompromising stand against the Church to secure salvation for the Christians of the world.
Erasmus, in contrast to Luther, used satire and humor in his attempt to reform with words. Although ridiculed by other theologians about his grammatical inquiries into the Vulgate, he saw words as essential to spiritual health. If Jerome had translated the Bible wrong, it must be corrected:
Why are we so precise as to our food, our clothes, our money matters and why does this accuracy displease us in divine literature alone? He crawls along the ground, (19)they say, he wearies himself about words and syllables! Why do we slight any word of Him whom we venerate and worship under the name of the Word? 
In addition to making divine literature accurate and making the Church see that accuracy, Erasmus used words to create satires that attacked the Church and called for improvement. In The Praise of Folly, Folly speaks of the Church:
As to the Supreme Pontiffs, . . . if they were even to contemplate the meaning of the name Pope-that is, Father-or of the title of Most Holy, then they would become the most humble and mortified of men. How many would then be willing to spend all their wealth and efforts to procure this position? . . . These forfeitures would be replaced by vigils, fasts, sorrows, prayers, sermons, education, weariness, and a thousand other bothersome tasks of the sort. We should also mention that a great many copyists, notaries, lobbyists, promoters, secretaries, muleteers, grooms, bankers, and pimps... would be out of jobs. ... Under the present system what work need be done is handed over to Peter or Paul to do at their leisure, while pomp and pleasure are personally taken care of by the Popes. 
These words illustrate Erasmus's displeasure with the hierarchy of the Church and are not the only words he used as weapons.
While Luther was willing to sacrifice peace for salvation, Erasmus argued that a love of peace was essential for a Christian. But the Catholic Church would not be reformed peaceably. Luther justified to Erasmus the need for strife in The Bondage of the Will:
It is constantly the case with the word of God that because of it, the world is thrown into confusion. Christ openly declares: "I come not to send peace but a sword" (Matthew 10,34). And in Luke: "I come to send you fire upon the earth" (Luke 12,49); so in Paul, "in tumults" (2 Corinthians 6,5) etc.... The world and its god cannot and will not bear the word of the true God. And the true God cannot and will not keep silence. Since these two gods are at war with each other, how can there be anything else throughout the whole world, but uproar?
Therefore, to wish to silence this turmoil is really to want to hinder the word of God and stop its course. For wherever it comes, the word of God comes to change and renew the world. ... It is the Christian's part to expect and endure these things. ... I see indeed, my dear Erasmus, that you deplore the loss of peace and concord in many of your books. ... But I am sorry that I find it necessary to teach so great a theologian as yourself these things like a schoolboy, when you ought to be a teacher of others. 
Erasmus, however, saw that strife as unchristian and asked for gentleness even in argument:
(20)Let no one misinterpret our battle. We are not two gladiators incited against each other. I want to argue only against one of Luther's teachings, illuminating, if this be possible, in the subsequent clash of scriptural passages and arguments, the truth, the investigation of which has always been the most reputable activity of scholars. There will be no invective, and for two reasons: it does not behoove Christians so to act, and moreover, the truth, which by excessive quarreling is often lost, is discovered with greater certainty without it. 
Erasmus did not want to lose the truth; he did not want to sacrifice his Christianity for theoretical differences.
Because Erasmus could not assert things of which he was not sure, because he fought with words, because he was tolerant, he could not stand with Luther: he did not lead the Reformation. Although he wanted to change the Church, he did not want to sacrifice what he saw as supremely Christian: peace. In his colloquy, The Complaint of Peace, he allowed Peace to speak of its own importance:
As Peace, am I not praised by both me and gods as the very source and defender of all good things? What is there of prosperity, of security, or of happiness that cannot be ascribed to me? On the other hand, is not war the destroyer of all things and the very seed of evil? 
But in the sixteenth-century Holy Roman Empire, peace, the peace Erasmus so loved, could not win. The Reformation sparked over a hundred years of war throughout Europe. It was not a time for peace-lovers; it was a time for religious arguers who cared more about their doctrines and dogmas than they did about what Erasmus characterized as Christianity.