וַיִּקַּ֨ח שְׁמוּאֵ֜ל אֶ֣בֶן אַחַ֗ת וַיָּ֤שֶׂם בֵּֽין־הַמִּצְפָּה֙ וּבֵ֣ין הַשֵּׁ֔ן וַיִּקְרָ֥א אֶת־שְׁמָ֖הּ אֶ֣בֶן הָעָ֑זֶר וַיֹּאמַ֕ר עַד־הֵ֖נָּה עֲזָרָ֥נוּ יְהוָֽה׃
Samuel nahm einen Stein und stellte ihn auf zwischen Mizpa und die Felsenspitze und nannte seinen Namen Eben Haêser [Stein des Beistandes], denn er sprach: Bis hierher hat uns der Herr beigestanden.
Rashi
Even Haezer [Lit. the rock of help]. This was not yet its name,2 Obviously, because they were soundly defeated now. for it was first called this name [later] in Shmuel's time, but here Scripture calls it by its future name.