Matthew 5:1-2: "And seeing the multitudes, he went up into a mountain: and when he was set, his disciples came unto him: And he opened his mouth, and taught them, saying...."

Luke 6:17, 20: "And he came down with them, and stood in the plain, and the company of his disciples, and a great multitude of people...came to hear him.. And he lifted up his eyes on his disciples and said..."

Was this sermon on a mountain, or on a plain? And just what was its content? Matthew and Luke appear to vary.

In terms of place, the Greek in Matthew is to be interpreted as referring not to "on a mountain" but "in mountain country" - it is a regional rather than a specific reference.

The issue of content is also easy to explain. When reckoning with any teaching of Jesus that appears in more than one gospel, one should observe the dictum that Jesus taught these same basic things, in slightly different forms, perhaps hundreds of times. As long as the basic message is intact, it matters not at all which "version" is recorded.

At the same time, Matthew's structure is as a "teaching" gospel, a manual with a structure designed with education in mind. Matthew has clearly designed the Sermon on the Mount as a compendium (which his readers, seeing the structure of his Gospel, would recognize), rather than as a straight historical report (like Luke's version would be expected to be, as he is reporting in the Hellenistic historiographic tradition).

Keener's commentary on Matthew explains:
> ...[A]ncient writers exercised the freedom to rearrange sayings, often topically. Writers who collected such sayings summarizing the thrust of a famous teacher's message (such as Epictetus' Encheiridion, Menander's epitome, or the Qumran Temple Scroll) called their collections "epitomes"; Matthew has exercised an analogous literary liberty, collecting many of Jesus' sayings on the topic of ethics, even if the precise comparison with Greek "epitomes" may be overstated.

Keener notes as well that rabbinic collections of sayings could vary on details just as the two sermon "versions" could. There is no need to resort to any other harmonizations, such as that Jesus said the same things twice, varying them by saying them once in the third person and the other in the first person.

In the introductory comments to Jesus’ oft’-quoted sermon recorded in Matthew chapters 5-7, the first verse sets the stage for His “astonishing teachings.” Matthew indicates that “seeing the multitudes,” Jesus “went up on a mountain, and when He was seated His disciples came to Him” (emp. added). When Luke gives the setting for Jesus’ masterful sermon, he says that Jesus “came down with them and stood on a level place” (emp. added). The question that has been asked by many people is why Matthew recorded Jesus preaching this sermon from a mountain, while Luke said it was while He stood on a level place. Could Matthew or Luke have made a legitimate geographical error here, or is there a reasonable explanation for the difference that exists?

First of all, for these passages to be contradictory one must assume the two sermons were delivered at the same place and at the same time. But, as H. Leo Boles stated in his commentary on Luke, this sermon “may have been repeated a number of times and Luke gives a record of the sermon which was repeated at some later time than the record given by Matthew” (1940, p. 134). It is more than possible that Jesus repeated His teachings on various occasions. He easily could have preached the beatitudes in Capernaum as well as in Cana. He could have taught the model prayer in both Bethany and Bethsaida. Who are we to say that Jesus preached the principles and commands found in Matthew 5-7 only once? There are some men today who travel to a different city nearly every week preaching the same sermons—and do so effectively. Could Jesus not have done something similar?

A more likely solution to this geographical “problem” is simply to understand that Matthew and Luke were referring to the same sermon, and that Jesus was preaching it while being both on a mountain and on a “plain” (KJV) at the same time. The word “plain” (tópou pedinoú) simply means “ level place” (Wycliffe, 1985), and is translated thusly in nearly all modern versions of the Bible. Since a mountain can have level places on it, no one can assert logically that Matthew 5:1 and Luke 6:17 are contradictory. I have been to the top of a mountain in Anchorage, Alaska, that is so level it is known as “Flattop Mountain.” To say Jesus stood on a level place on a mountain is no oxymoron.

Luke 6:17
—Why does Luke say Jesus gave this sermon on a level place when Matthew declares it was given on the mountain?
Problem:
Luke affirms that Jesus “stood on a level place” when He gave this famous sermon, but Matthew says “He went up on a mountain” to deliver it (
Matt. 5:1
). How can this discrepancy be resolved?
Solution:
Granted that the two accounts are referring to the same event (see comments on
Luke 6:20
below), they can be reconciled by noting that the mountain only refers to the
general area
where everyone was, while the level place denotes the
particular spot
from which Jesus spoke. It says “He
stood
on a level place.” It does not say all the people were
seated
in a level place. A level place from which to preach to a multitude on a mountain side would make a natural amphitheater.

Luke 6:17
—Why does Luke say Jesus stood to teach them when Matthew declares that He sat to teach them?
Problem:
Luke says that Jesus “stood on a level place” to preach. But Matthew recorded that “when He was seated ... He opened His mouth and taught them” (
Matt. 5:1–2
).
Solution:
These references may be of slightly different times during the same event. One possibility is that Matthew’s reference is to the beginning of the event when “His disciples came to Him ... and [He] taught them” (
Matt. 5:1–2
). Then when the “great multitude [that] followed Him” gathered to listen in, Jesus would naturally want to stand to project His voice so that all could hear, as Luke records.
Another possibility is that Luke’s reference to Jesus’ standing is before He gave the sermon while He is still healing people (
Luke 6:17–19
). Then, since “the whole multitude sought to touch Him” Jesus may have found a place to sit where “He lifted up His eyes toward His disciples and said ... [His message]” (
6:20
). This fits the order given in Luke and would also explain why Matthew declares that Jesus was sitting when He spoke to His disciples. In any event, there is no irreconcilable difference in the two accounts, even assuming they both refer to the same occasion.