וַיֹּ֤אמֶר יְהוָה֙ אֶל־מֹשֶׁ֔ה הִנְּךָ֥ שֹׁכֵ֖ב עִם־אֲבֹתֶ֑יךָ וְקָם֩ הָעָ֨ם הַזֶּ֜ה וְזָנָ֣ה ׀ אַחֲרֵ֣י ׀ אֱלֹהֵ֣י נֵֽכַר־הָאָ֗רֶץ אֲשֶׁ֨ר ה֤וּא בָא־שָׁ֙מָּה֙ בְּקִרְבּ֔וֹ וַעֲזָבַ֕נִי וְהֵפֵר֙ אֶת־בְּרִיתִ֔י אֲשֶׁ֥ר כָּרַ֖תִּי אִתּֽוֹ׃
And the LORD said unto Moses: ‘Behold, thou art about to sleep with thy fathers; and this people will rise up, and go astray after the foreign gods of the land, whither they go to be among them, and will forsake Me, and break My covenant which I have made with them.
Read halakhic rulings (Jewish law) on Deuteronomy 31:16: and classical halakhic sources.