The following information is derived from a paper by Eric Ottenheijm of the University of Utrecht presented at the 2010 Society of Biblical Literature in the Matthew section.
In Matthew 5:1, Yeshua went up on “the mountain.” No one knows which mountain, although there is a lovely hill which is the traditional spot. More important than a physical location, though, is understanding the allusion of “the mountain.” There are a number of mountains of great significance in the Hebrew Bible. The echoes of Exodus and Isaiah in particular add depth and meaning to the Sermon on the Mount.
For a long time, it has been recognized that Yeshua’s ascending the mountain to deliver the Sermon on the Mount has echoes of Moses ascending Sinai to receive and then deliver the Torah. There is a long tradition of viewing the Beatitudes, for example, as a sort of new Ten Commandments.
Dale Allison, in The New Moses: A Matthean Typology, gives a few reinforcements to the Sinai imagery: (1) “went up the mountain” in the LXX (Greek or Septuagint version of the Bible) is used 18 times of Moses, (2) Yeshua sat on the mountain and Moses “dwelt” or “sat” forty days according to Deuteronomy 9:9, (3) other Jewish literature such as 4 Ezra 14 uses the “sat” motif to make a character echo Moses, and (4) Matthew 8:1 continues to echo language about Moses.
Eric Ottenheijm shows, however, that more than Moses is going in in the mount of the Sermon.
“How beautiful upon the mountains are the feet of him who brings good tidings, who publishes peace, who brings good tidings of good, who publishes salvation, who says to Zion, ‘Your God reigns,’” says Isaiah in 52:7.
“Get you up to a high mountain, O Zion, herald of good tidings,” is Isaiah’s word in 40:9.
“The Spirit of the Lord God is upon me, because the Lord has anointed me to bring good tidings to the afflicted,” Isaiah says in 61:1.
The mountain of Isaiah is the mountain of good news. The one whose feet are on it delivers good news to the poor. “Blessed are the poor,” says Yeshua in the Sermon.
Ottenheijm points out a few things about Isaiah and Matthew:
(1) Matthew quotes and alludes to Isaiah more than any other book.
(2) Matthew 4:12 – 5:11 (the larger section surrounding 5:1) begins and ends with Isaiah references (see below).
(3) Matthew is not the only Jewish literature combining Isaiah 52:7 with 40:9 and 61:1 (see below).
Is this a denial of the Moses/Sinai theme in Matthew? Not at all. Ottenheijm says that first, Isaiah took the mountain theme from the story of Israel and gave it a new twist and then Matthew took up Isaiah’s mountain theme, which already had Moses overtones, and gave it still a new twist:
Moses/Sinai/Torah –> messenger/mountain/good news in Isaiah –> Yeshua brings good news on the mountain.
In the time of Yeshua and Matthew, people read the Torah looking for connection to God and an end to the exile. They also read Isaiah this way, finding Isaiah to be a sort of messianic handbook of the last days. It is not hard to imagine those who first heard Matthew’s version of the Sermon read aloud connecting Yeshua with the messenger of good news in Isaiah. God sends his Torah and his good news from “the mountain.”
APPENDIX A: Isaiah in Matthew 4:12 – 5:11 (derived from Ottenheijm’s paper):
Matt 4:12-17 Galilee of the gentiles, Isaiah 8:23 – 9:1.
Matt 4:23 Good news, allusion to Isaiah 52:7 and 40:9.
Matt 5:1 Yeshua ascends the mountain and sits down.
Matt 5:3-5 First two Beatitudes compare to Isaiah 61:1-3.
Matt 5:11 Echoes Isaiah 51:7.
APPENDIX B: Early Jewish Texts Combining Isaiah 52:7; 61:1-3; and 40:9 (abridged from Ottenheijm):
–Psalms of Solomon 11.
–Tanhuma Toledot 14 combines the idea of Messiah and Isaiah 52:7.