Is Jesus’s visit in 3 Nephi just the Sermon on the Mount again?

In chapter 11 He shows His wounds and gives authority to baptize. In chapters 17 and 18 He heals people, blesses children, and gives the sacrament.

These are distinct episodes in the narrative. The New Testament has related themes, so the claim is about what the Bountiful account contains.

The sermon itself is all there is to discuss.

The sermon occupies chapters 12–14. Read the chapters before and after it to see what the narrative adds.

Every Gospel gives it in exactly the same words, so there’s nothing to explain.

Luke’s version is shorter and lacks the law-and-prophets clause. The closer wording and order in Matthew are real evidence to consider.

It matters. Matthew and 3 Nephi match closely, while Luke gives it more briefly. Any account of the English text has to explain that.

You granted the strongest textual observation before considering what might explain it.

In Matthew, Jesus speaks of coming to fulfill the law. At Bountiful, the risen Jesus says it has been fulfilled in Him and explains what still remains of Israel’s covenant.

You identified a difference the narrative itself develops. Read 3 Nephi 12 with Jesus’s explanation in chapter 15.

The wording changes are all cosmetic.

The shift from purpose to fulfillment matters because Jesus then explains which obligations and promises remain.

Yes. An author using Matthew could never have added material that fits the setting.

An author can adapt a source. The additions establish what differs. Identifying the process that produced the text takes other evidence.

It shows the visit adds something. The origin question still needs an account of both the distinctive material and the shared English and order.

You kept the literary and historical questions separate while taking both seriously.