כִּ֣י חֶשְׁבּ֔וֹן עִ֗יר סִיחֹ֛ן מֶ֥לֶךְ הָאֱמֹרִ֖י הִ֑וא וְה֣וּא נִלְחַ֗ם בְּמֶ֤לֶךְ מוֹאָב֙ הָֽרִאשׁ֔וֹן וַיִּקַּ֧ח אֶת־כָּל־אַרְצ֛וֹ מִיָּד֖וֹ עַד־אַרְנֹֽן׃
For Heshbon was the city of Sihon the king of the Amorites, who had fought against the former king of Moab, and taken all his land out of his hand, even unto the Arnon.
Read halakhic rulings (Jewish law) on Numbers 21:26: and classical halakhic sources.