(ה) וַיְדַבֵּ֣ר הָעָ֗ם בֵּֽאלֹקִים֮ וּבְמֹשֶׁה֒ לָמָ֤ה הֶֽעֱלִיתֻ֙נוּ֙ מִמִּצְרַ֔יִם לָמ֖וּת בַּמִּדְבָּ֑ר כִּ֣י אֵ֥ין לֶ֙חֶם֙ וְאֵ֣ין מַ֔יִם וְנַפְשֵׁ֣נוּ קָ֔צָה בַּלֶּ֖חֶם הַקְּלֹקֵֽל׃
(ו) וַיְשַׁלַּ֨ח ה' בָּעָ֗ם אֵ֚ת הַנְּחָשִׁ֣ים הַשְּׂרָפִ֔ים וַֽיְנַשְּׁכ֖וּ אֶת־הָעָ֑ם וַיָּ֥מָת עַם־רָ֖ב מִיִּשְׂרָאֵֽל׃
(ז) וַיָּבֹא֩ הָעָ֨ם אֶל־מֹשֶׁ֜ה וַיֹּאמְר֣וּ חָטָ֗אנוּ כִּֽי־דִבַּ֤רְנוּ בַֽה' וָבָ֔ךְ הִתְפַּלֵּל֙ אֶל־ה' וְיָסֵ֥ר מֵעָלֵ֖ינוּ אֶת־הַנָּחָ֑שׁ וַיִּתְפַּלֵּ֥ל מֹשֶׁ֖ה בְּעַ֥ד הָעָֽם׃
(ח) וַיֹּ֨אמֶר ה' אֶל־מֹשֶׁ֗ה עֲשֵׂ֤ה לְךָ֙ שָׂרָ֔ף וְשִׂ֥ים אֹת֖וֹ עַל־נֵ֑ס וְהָיָה֙ כָּל־הַנָּשׁ֔וּךְ וְרָאָ֥ה אֹת֖וֹ וָחָֽי׃
(ט) וַיַּ֤עַשׂ מֹשֶׁה֙ נְחַ֣שׁ נְחֹ֔שֶׁת וַיְשִׂמֵ֖הוּ עַל־הַנֵּ֑ס וְהָיָ֗ה אִם־נָשַׁ֤ךְ הַנָּחָשׁ֙ אֶת־אִ֔ישׁ וְהִבִּ֛יט אֶל־נְחַ֥שׁ הַנְּחֹ֖שֶׁת וָחָֽי׃
(5) and the people spoke against God and against Moses, “Why did you make us leave Egypt to die in the wilderness? There is no bread and no water, and we have come to loathe this miserable food.”
(6) The LORD sent seraph serpents against the people. They bit the people and many of the Israelites died.
(7) The people came to Moses and said, “We sinned by speaking against the LORD and against you. Intercede with the LORD to take away the serpents from us!” And Moses interceded for the people.
(8) Then the LORD said to Moses, “Make a seraph figure and mount it on a standard. And if anyone who is bitten looks at it, he shall recover.”
(9) Moses made a copper serpent and mounted it on a standard; and when anyone was bitten by a serpent, he would look at the copper serpent and recover.
Tosafot explain that as tractate Bava Metzia follows tractate Bava Kamma, the halakhot of found items are elucidated in this chapter as a continuation of the topics discussed in the last chapter of Bava Kamma, which discussed the division of items between litigants by means of an oath, which is also the ruling in the mishna here (see Shita Mekubbetzet). The Rosh explains that because there is a suspicion of theft in this case, these matters are juxtaposed with the halakhot of theft, which are described at length in Bava Kamma.
MISHNA: If two people came to court holding a garment, and this one, the first litigant, says: I found it, and that one, the second litigant, says: I found it; this one says: All of it is mine, and that one says: All of it is mine; how does the court adjudicate this case? This one takes an oath that he does not have ownership of less than half of it, and that one takes an oath that he does not have ownership of less than half of it, and they divide it.