וַיִּקְרָ֤א שְׁמוּאֵל֙ אֶל־יְהוָ֔ה וַיִּתֵּ֧ן יְהוָ֛ה קֹלֹ֥ת וּמָטָ֖ר בַּיּ֣וֹם הַה֑וּא וַיִּירָ֨א כָל־הָעָ֥ם מְאֹ֛ד אֶת־יְהוָ֖ה וְאֶת־שְׁמוּאֵֽל׃
So Samuel called unto the LORD; and the LORD sent thunder and rain that day; and all the people greatly feared the LORD and Samuel.
Read halakhic rulings (Jewish law) on I Samuel 12:18: and classical halakhic sources.