וַיַּ֣עַל מִשָּׁ֔ם אֶל־יֹשְׁבֵ֖י דְּבִ֑ר וְשֵׁם־דְּבִ֥ר לְפָנִ֖ים קִרְיַת־סֵֽפֶר׃
And he went up thence against the inhabitants of Debir—now the name of Debir beforetime was Kiriath-sepher.
Read midrashic interpretation of Joshua 15:15: and classical rabbinic exegesis.