וַיֹּ֨אמֶר מֹשֶׁ֜ה אֶל־הָֽאֱלֹהִ֗ים הִנֵּ֨ה אָנֹכִ֣י בָא֮ אֶל־בְּנֵ֣י יִשְׂרָאֵל֒ וְאָמַרְתִּ֣י לָהֶ֔ם אֱלֹהֵ֥י אֲבוֹתֵיכֶ֖ם שְׁלָחַ֣נִי אֲלֵיכֶ֑ם וְאָֽמְרוּ־לִ֣י מַה־שְּׁמ֔וֹ מָ֥ה אֹמַ֖ר אֲלֵהֶֽם

Moses said to God, “When I come to the Israelites and say to them, ‘The God of your fathers has sent me to you,’ and they ask me, ‘What is His name?’ what shall I say to them?” 

וַיֹּ֤אמֶר אֱלֹהִים֙ אֶל־מֹשֶׁ֔ה אֶֽהְיֶ֖ה אֲשֶׁ֣ר אֶֽהְיֶ֑ה וַיֹּ֗אמֶר כֹּ֤ה תֹאמַר֙ לִבְנֵ֣י יִשְׂרָאֵ֔ל אֶֽהְיֶ֖ה שְׁלָחַ֥נִי אֲלֵיכֶֽם

And God said to Moses, “Ehyeh-Asher-Ehyeh.” He continued, “Thus shall you say to the Israelites, ‘Ehyeh sent me to you.’” 

Exodus 3, 13-14

(Sefaria)