וַיֹּ֣אמֶר שְׁמוּאֵ֔ל וְלָ֖מָּה תִּשְׁאָלֵ֑נִי וַיהוָ֛ה סָ֥ר מֵעָלֶ֖יךָ וַיְהִ֥י עָרֶֽךָ׃
And Samuel said: ‘Wherefore then dost thou ask of me, seeing the LORD is departed from thee, and is become thine adversary?
Read midrashic interpretation of I Samuel 28:16: and classical rabbinic exegesis.