Why had the Nephites begun baptizing infants? Why did this start? We do not know exactly, but there may be several possibilities.
We can assume that the Nephites practiced circumcision before the coming of Christ, since they were strict in keeping the law of Moses and were descendants of the House of Israel through Manasseh (Lehi), as well as probably Ephraim (Ishmael), and Judah (Zoram and Mulek). Circumcision, if you go back into the Old Testament, served several purposes and one of them in Exodus 4, was that if you are circumcised, it will turn away threats of death and will give you victory. Now if you have a bunch of people who are taking the offensive and going out into the battlefield and they want to enhance their chances of victory, maybe they started circumcising people as a way of imploring God to help them all.
With the coming of Christ and the introduction of baptism as the new sign of the covenant, they would not have been circumcising at that time, and so, they may have thought, “We ought to try this.” After all, before Joshua could lead the Israelites of his day into the Promised Land, the males were all circumcised so that they would be given victory. Maybe the Nephites in Mormon’s day began doing this as a way of enhancing their chances with victory by expressing this as an additional sign of covenant, and although they had it wrong, maybe they were trying to bind the Lord to help them. In addition, since baptism was a sign of spiritually dying and being reborn of God, using infant baptism as a spiritual symbol of death and rebirth is at least better than actually using infant sacrifice, which was practiced in several places in the ancient world. Whatever the background or context or their arguments may have been, the Nephites at this time started the practice of baptizing young children. Perhaps, since they circumcised newborn male infants, that ceremony influenced them to move baptism to that point in a child’s life as well.
In the history of Christianity in the Mediterranean world, the baptizing of infants was not done until the fourth Century, as the written and archaeological records are fairly clear. For example, there are thousands upon thousands of Christian burials in the catacombs under Rome, and dates are given for most of these burials. The dates given are usually the birth date, the baptism date, and the death date, and this information allows for analysis of their baptismal customs.
In the case of burials from the second and third centuries, there is a birth date, and then quite some time later, a baptism date, about the time when you would expect for a teenager, a young adult, or a convert—and many but not all of these people were converts to Christianity. However, there are no infant baptisms shown in these years, and the death dates were normally long after the baptism.
In the fourth century, there occurred a change in the routine. For records early in that century, there began to appear a sequence of a birth date, and then a baptism date very much later, followed a couple days later by the death date. Then there was yet another change: the birth dates began to appear with a week later the baptism date, then eventually a death date long after. Thus, it certainly appears that infant baptisms either began or became much more common about the middle of the fourth century AD.
The German scholar, Joachim Jeremias, who analyzed these dates, surmised that people had wanted to have their sins washed away right before they died, so that they could go right to heaven without any blemishes on their record. They were delaying baptism wrongly, so they could treat it as a last unction before death and not worry about living sinful lives. The reaction of the church leader in Rome was to begin baptizing everyone as infants to solve that problem. In their attempt to solve one problem, they created a new one. Christian theologians would rationalize infant baptism as a sign of the covenant, just as circumcision of infant boys eight days after birth had become a sign of the covenant of God with Abraham among the Jews. But that was always understood as a birthright, not as a rebirth following the remission of sins.
From the Nephite world, there is no information about why they began infant baptism, but a totally new pattern had arisen, and Mormon was astonished, even offended by it. He was appalled at how wrongly they were thinking.
Parents may have begun having their children baptized out of fear. In the absence of guidance from the Holy Ghost, people do what appears logical at the time. Perhaps some parents were getting really worried that their children were going to die. They were starving and were heading for gruesome times of warfare that did not spare the children. Parents may have been afraid that the children would never get a chance to be baptized. This may have been well intended. There are usually motivations that cause such changes, but whatever motivated this practice, Mormon did not like it. Can there be any doubt that Mormon thought that this was a bad idea? Look at the words he used, “A gross error,” “a solemn mockery,” used twice. He claimed that anyone who would do this was in the gall of bitterness. He saw this as an awful wickedness.
Mormon was most concerned because infant baptism very clearly denies the whole process of repentance that allows the whole process of the mercy of Christ to operate. It abrogates the whole purpose of Christ’s Atonement, and thus it creates a bigger problem within the entire church. If people are not willing to teach their children to repent so that they can be baptized and then they cease repenting, wicked conditions would certainly ensue.
Mormon’s response leads to an important question: What does a person’s attitude about the baptism of little children reveal about a person’s spiritual state and his understanding of the gospel? Mormon wanted people to understand how the gospel really worked. He declared that they were denying Christ’s Atonement by not recognizing that children are alive in Christ. They may have been administering ordinances, but they had lost the point of them.
One may wonder if in an effort to have power, they had started their own splinter church organizations by deciding to do something differently in order to appease the people and to stay in control of the situation. Such people, one might say, would have the appearance of good efforts, but they would lack the authority to make such changes. In response, Mormon was quite harsh, and did not identify any righteous reason for the change. In Mormon 3:2, the Lord says to Mormon, “Cry unto my people, repent ye … and build up again my church,” which may indicate that there actually had arisen another church competing for the people’s minds and hearts. Forming alternative religious orders, as with the Order of Nehors, had a long history among the Nephites.
Book of Mormon Central, “Why Did Moroni Include Mormon’s Condemnation of Infant Baptism? (Moroni 8:12),” KnoWhy 253 (December 15, 2016).