Sotah Chapter 7, Mishnah 5: "Berachos u'kelalos keitzad" - the blessings and the curses that were pronounced on Mount Gerizim and Mount Eival, how were they done? Unlike the previous mishnayos, where the word "keitzad" meant "from where do we know" - from where do we know that this must be said in the holy tongue - here the word carries its plain meaning: how was it done, how was the mitzvah carried out, and what was the order of the procedure.
Identifying the place:
The Mishnah opens: "Keivan she'avru Yisrael es haYarden u'va'u el Har Gerizim v'Har Eival she'b'Shomron, sheb'tzad Shechem, she'eitzel Elon Moreh" - once the Jewish people crossed the Jordan River, they came to Mount Gerizim and Mount Eival in the Shomron, alongside the city of Shechem, near Elon Moreh. From where do we know that their location is near Elon Moreh and Shechem? From a gezeirah shavah between two verses:
"Halo heimah b'ever haYarden" - at the time this was told to them in the Chumash, the Jewish people were on the eastern side of the Jordan, and the mountains were "across the Jordan," on its western side, in the Land of Israel, where they later stood. And it says there that this was "near Elon Moreh."
"U'lehalan hu omer" - in Parashas Lech Lecha it says: "Vaya'avor Avram ba'aretz ad mekom Shechem... ad Elon Moreh".
From here: "Mah Elon Moreh ha'amur lehalan Shechem, af Elon Moreh ha'amur kan" - just as the Elon Moreh mentioned in connection with Avraham refers to Shechem, so too the Elon Moreh mentioned here in connection with Mount Gerizim and Mount Eival is near Shechem.
The positions of the tribes and the Ark:
Having identified the place, the Mishnah describes the order of the assembly:
"Shishah shevatim alu l'rosh Har Gerizim v'shishah shevatim alu l'rosh Har Eival" - six tribes at the top of each mountain.
"V'haKohanim v'haLevi'im v'ha'aron omdim l'matah ba'emtza" - the Kohanim, the Levi'im and the Ark stood below, in the valley between the two mountains.
"HaKohanim makifin es ha'aron v'haLevi'im es haKohanim" - the Kohanim surrounded the Ark, and the Levi'im surrounded the Kohanim.
"V'chol Yisrael mikan u'mikan" - all of Israel stood on both sides, as it says in the Book of Yehoshua: "And all Israel and its elders and its officers and its judges were standing on this side and on that side of the Ark."
The blessings and the curses:
The Levi'im "hafchu p'neihem k'lapei Har Gerizim u'faschu bivrachah", and the Mishnah brings one of the blessings: "Baruch ha'ish asher lo ya'aseh pesel u'masechah", "v'eilu v'eilu onin amen" - both the tribes on Mount Gerizim and the tribes on Mount Eival would answer amen. In the Torah itself only the "arur," the curse alone, is recorded, and from the Mishnah we learn that before each curse a blessing was pronounced.
Afterward the Levi'im turned their faces toward Mount Eival and began with the curse: "Arur ha'ish asher ya'aseh pesel u'masechah", and both groups of tribes on either side would answer amen. This is how they proceeded until they completed all the blessings and the curses.
The stones, the altar and the writing of the Torah:
Afterward they took the stones that they had brought up out of the Jordan - twelve stones - built an altar from them, plastered it with lime, and wrote upon it all the words of the Torah in seventy languages, as the verse says that they should write "ba'er heitev," which is explained to mean in seventy languages. It is worth noting that the Rishonim disagree as to whether the entire Torah was in fact written - in which case it was done miraculously - or whether only a list of mitzvos was written.
The Mishnah adds that afterward they took the stones, traveled, came and lodged with them in their place in Gilgal, where the Jewish people were encamped. It emerges that the stones were on Mount Gerizim and Mount Eival only temporarily.
In summary: in this Mishnah we learned the order of the assembly of the blessings and the curses: identifying the place near Shechem and Elon Moreh by means of a gezeirah shavah from Avraham Avinu; six tribes standing on each mountain with the Kohanim, the Levi'im and the Ark in the valley between them; the blessing being pronounced toward Mount Gerizim and the curse toward Mount Eival with everyone answering amen; and finally the building of the altar from the stones of the Jordan, its plastering with lime and the writing of the words of the Torah in seventy languages, until the stones were transferred to their place in Gilgal.